What is .md3 and .bsp from Quake III Arena and is q3data.exe part of official modding tools and does anyone have an idea to explore 3D models and animations and develop custom character models .md3 and map models .bsp?

Here is the MD3 file format specification written by TJHui: https://rewiki.miraheze.org/wiki/Md3

Here is the game's source code uploaded to GitHub by id Software: https://github.com/id-Software/Quake-III-Arena

and here is the official modding tools (with source code) that allows authors to compile ASE or 3DS (used for old versions of 3ds Max) files into .md3 using Q3Data and Q3Radiant.

quake3arena_md3bsp.rar quake3arena_tools.rar quake3arena_toolssourcecode.rar

Yes sir. As you mentioned, MD3 tools are already well‑established, and there are 3ds Max plugins that support this format. Modifying MD3 files is completely achievable with them, so why are you posting this question?Besides model vertex coordinates, MD3 also contains attachment point data (such as markers for bullet firing). Its structure is very straightforward, and I believe the tools mentioned above are sufficient for your editing needs.

2 hours ago, KuWuniss6 said:

Modifying MD3 files is completely achievable with them, so why are you posting this question?