I am not familiar with chocolate doom what makes it better than any other doom source port?
There are many good source ports of quake, I always liked darkplaces but it intentionally and willfully tries to push improvements so not really for purists. There is stuff like fitzquake/quakespasm that stays much closer to vanilla quake and if you like quakeworld ftequake.
Chocolate Doom attempts to replicate the original Doom experience in a modern source port, without the embellishments, bug fixes, and features offered by source ports like GZDoom. It's like the difference between building a modern clone of the Amiga 500, hewing as close to the original designs as possible, and building a "modern Amiga" with a PPC CPU, modern GPU, AmigaOS 4.x support, etc. Sure, the second is neat, but some people want to work within the exact constraints and quirks of the first.
> I am not familiar with chocolate doom what makes it better than any other doom source port?
The earliest doom variants once the source code released started adding features that weren't faithful to the original dos version 1.9.
Even Boom which was a pretty conservative codebase that focused on limit removal for level editing added weird things like weapon recoil pushing the player back when you shoot a weapon.
So chocolate doom's name is wordplay on "vanilla doom" - it's the version of doom we all played in the 90s just updated with current i/o libraries (libSDL) so it can run on modern platforms.