Installing software in /usr, /usr/src?

Question

linux

In the /home section, I would like to store only my data files and scripts, and user configs. I don’t want to fill it with directories with downloaded third-party software (IDEs like PyCharm, virtual environments and third-party frameworks in Python, some kind of application software and games). In addition to visual rubbish in the form of extra folders, they take up a lot of space, making it difficult to archive /home.
Linux has a /usr partition, which seems to be specifically for installing software.
Can it be installed there? If so, to which subdirectory? How to set up permissions to run without any perversions, just as easy as from / home?
There is also /usr/src. Judging by articles from a decade ago, this section was occasionally used to compile the kernel. As I understand it, it is no longer needed by a regular user? Or can Python environments be moved there? Whether there will be problems with the rights?
For example, PyCharm. The package is downloaded as an archive. On first run, it creates configs in /home. And then, in principle, the directory itself with executable files can be moved to another location and renamed.

Answer 1

In Linux, programs are not installed in separate folders. All binaries go to /usr/bin, libraries to /usr/lib, resources to /usr/share, etc.
This is usually done automatically by the package manager.
When installing not through a package manager, they usually install to /usr/local/bin, /usr/local/lib, etc.
There are developers who could not master FHS and throw everything into one folder. Then it is usually installed in /opt (/opt/clion, /opt/sublime_text_3, etc).

Answer 2

Well, I just put all sorts of IDEs and stuff in a separate section, for example / data / Tools, so as not to demolish it when reinstalling the system and not clog / home. For convenience, I create a link ~/Tools => /data/Tools.