Sodium is the one with the most impact, but there are other good ones out there. So its not just one mod, but multiple. https://github.com/NordicGamerFE/usefulmods/tree/main/Performance

If you want a modpack that gives you performance, check out https://modrinth.com/modpack/sop

simply optimized modpack

I dont have ready list of performance improving mods but I would look at mods installed by rlcraft. The modpack is so heavy on resources they tend to add many mods for performance improvement.

I don't know about best, but give Fabulously Optimized a try.