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Python versions are not changing despite activating virtual environment in WSL2

Background:
In WSL2 (ubuntu 20.04) I created a python virtual environment inside a directory. Using the command python3 -m venv venv my system's python version was set to python3.11 (after downloading) via sudo update-alternatives --config python3 and then choosing the version. I noticed I was having some errors of missing modules when I started WSL2 (happening after a computer restart), I read this was because I was using a different python version than the one ubuntu 20.04 came with so I switched back to 3.8 via the config menu as before. I am also using VS code that's connected to my WSL2.
These are some of the contents of my venv directory: venv/bin/python venv/bin/python3 venv/bin/python3.11 venv/bin/pip venv/bin/pip3
Question:
After activating my virutal env via source venv/bin/activate, when I do python3 --version I still get a version of 3.8.10 despite creating the virtual environment with 3.11. I was able to get the interpretor set to 3.11 on VS code.I know I was in the virtual environment since my command prompt had (venv) in front. I went into the python console while in the virtual env and did import sys and sys.path this was my output ['', '/usr/lib/python38.zip', '/usr/lib/python3.8', '/usr/lib/python3.8/lib-dynload']. Why isn't the python version changing, am I misunderstanding something or did I not do something correctly? Seems like pip isn't working either but works when I switch my system python to 3.11 (I tried installing it on 3.8 but it said it was already installed).
Solved:
Answered below, just re-created the virtual env while making sure my system python version was 3.11 (may have been some mixup earlier).

By changing the selection in sudo update-alternatives --config python3 you change the selected python version also for the chosen vitrual environment (at least when using venv, it might be different with other tools).
That can cause issues, because when creating a new virtual environment envname using venv from a specific python version xx.xx, a directory named pythonxx.xx is created in /envname/lib/, and inside it a directory named site-packages that contains the packages installed by the pip of this specific environment.
So changing back to the original python version of the environment through sudo update-alternatives --config python3 should solve the issue, and probably the errors of missing modules are due to the incompatibility of the current selected python version with the original version which you installed the virtual environment from.
Personally, to avoid confusing, I name my virtual environments with the python version as a suffix, e.g envname_py3.11.1. But there might be a better method which I am not aware of.

I deleted my venv directory and recreated my virtual environment while on python3.11. This has resolved my issue.

Creating Python virtual environment in different version than installed on Windows

To run some script I need specific version of python (3.7.1).
On my PC I have python 3.7.3
For creating virtual environment I am using:
python -m venv virtual
Which gives me fully functional python but in version 3.7.3 and I need 3.7.1
How can this be achieved?

virtualenv can only create environments for versions of python installed on the machine.
You may install multiple versions in parallel on windows then select which one to use.

Just install Python 3.7.1. Assuming you are using virtualenv, create your environment as:
virtualenv -p /home/username/opt/python-3.7.1/bin/python Project_Name

problems creating virtualenv when installing two different versions of Python

I have installed Python 2.7, pip and virtualenv on my computer and I have created a virtual environment with this same version of Python. I installed some packages in this new virtual environment too.
Later, I decided to install Python 3.6 on the same computer to create a virtual environment that works with version 3.6. I downloaded Python 3.6 and installed it by selecting Add Python 3.6 to PATH and Install for All users and I selected the option to automatically install pip. As I had previously installed virtualenv, I have not had to reinstall it. Should I?
The problem is that, once installed, when creating a virtual environment I've got an error.
As I already had a version of Python installed I have specified that I want to use Python 3.6 in the virtual environment that I am creating:
virtualenv env2_py36 -p c: \ Python36 \ python.exe
The error already says that this usually happens when you install more than one version of Python on the same computer and warns that it is necessary to check the option Install for All Users to work (as I did) and also recommends placing the appropiate PythonXX.dll file in the Scripts folder of the virtual environment. However, I see that there is already a python36.dll file there.
Could anybody tell me what should I do to fix this problem?
On the other hand, I had previously created another virtual environment using Python 2.7. I use PyScripter to run my scripts but I don't know how to connect PyScripter to my virtual environment. It's still connected to the Python2.7's system installation.

This works for me:
virtualenv --python=python3.6 yourenvname
(3.6 is the current latest version of Python, but you can use whichever version you'd like.)

How to use a virtual environment

Using Python I require both python 2.7 and python 3.5 for different packages. I am trying to install the following package NepidemiX. I get an error when I do this as I have a newer version of python installed.
To combat this I am trying to create a virtual environment. To do this I am using the virtualenv package.
I have created and activated this and am now faced with
(my_project)Your-Computer:your_project UserName$)
In my terminal.
How do I now proceed to install my package from here? Do I need to install python 2.7 in this environment first, or do I simply copy the desired package into the environment ... ?
Please could you instruct me how to correctly set this up?
Many thanks!

Virtual environment is only for libraries. It uses python versions installed on your computer. You can specify the version of python by using the -p attribute while creating the environment, for ex. virtualenv -p python3 env creates a python 3 enviroment (provided you have it installed in your computer and on the PATH). Check this answer.
After you activate the environment (source /env/bin/activate), just pip install libraries, and the environment takes care of installing the correct version.

virtualenv not setting virtual environment

in debian based Linux i am trying to uninstall a package installed by pip but for removing it after search it says it will only uninstall it in virtual environment after install virtualenv and upgrading it to version 15.0.3 i run command
virtualenv --no-site-packages /usr
then error occured that it is being run by interpreter and please use system python to execute the script
then i changed the python version via -p flag to python3 then it says the same msg that already using the python3 interpreter i also used simple python version still no luck
i trolled the stackoverflow & google but got no valid answer

Finally after searching and experimenting a lot I just owerwrited the new version of twisted by downloading the old one some of the files it did not deleted however all packages in the system started using newly downloaded old version of twisted!