Describe the bug

COMPILING.md, CONTRIBUTING.md and other documentation is incomplete and unclear for new contributors.
To Reproduce

Just one simple example:
There are several make commands suggested in the documentation, but nowhere is stated that you have to run qmake Jamulus.pro before you can use any make command like make clang_format.

Also there are many prerequisites mentioned like Qt, Visual Studio and XCode, but nowhere is mentioned which versions they should be and where/how to get them (some are very hard to find!) and which options to install (many are not default, but some are essential).
Even some very essential tools (like git and clang-format) aren't even mentioned at all.
Also the "more information" links often send you in circles, referring back to where you came from.
i.e. CONTRIBUTING.md points to this page which contains not much more information than a link back to CONTRIBUTING.md.
Expected behavior

For a new contributor it should at least be clear what to install, with what options, and where to get it.
For the "old" contributors It may all seem seem obvious, but for newbies, like me, even as a very experienced software engineer, It is a real struggle to get everything installed and working.
Screenshots

Operating system

n.a.
Version of Jamulus

n.a.
Additional context