F-Droid APK and signature


Dear members of the F-Droid community,

I am happy to be here!
I downloaded the Apk of F-Droid from this homepage. There is also a button showing the signature. I thought it is for checking that the correct file arrived on my computer.
Could anyone tell me if this is right and how it works to check the signature? (with GnuPGP.)
I am a beginner please keep it in mind that I need a detailed describtion to understand everything.

Thank you very much and greetings,


Answered here (in German).