@louislou24, you should read all that @billsimon has contributed (here and elsewhere), he is our goto dude when it comes to deploying FreePBX on Debian based systems, His recipes work perfectly.
Given your reticence to ‘just use the Distro’ , you have a long row to hoe if you ignore this advice. On the other hand absorb all the knowledge offered and you will soon be enlightened.
(Please don’t be a Bull in a china shop, please stop the ‘posting diarrhea’ , some of us get annoyed when you just refuse to read the readily available FM’s )