Ruleset Command line in virtual env?

Thank you for the answer,
yes i need Python3 and i am running checkmk 1.7 now, forgot to mention this.

I have never created a wrapper script, when i am going to install the package it gives me
WARNING: Target directory /omd/sites/gvm/local/lib/python3/__pycache__ already exists. Specify --upgrade to force replacement.

But even if i get this running, you said i need to place the wrapper script in /.../plugins ?
Do i need to do something else with it that checkmk finds it as an active check?

I am sorry for asking basics like this but i am new to checkmk and python