Hello and welcome to the forum!
There's lots of releases of source, clients, server files, tools etc here on the forum! Look around in here and you will find the stuff you need to get started!
Also, lots of people nowdays uses AI to aid/asisst in server setups, to bug fixing/new feature implementations, so that can be super helpful aswell.
For AI's people use Opus 5.5 or GPT Astra 6 (in the codex app or in the Claude App)