UsefulMods VS ActuallyUsefulMods

There's tons of mods that do what Optifine did now. https://github.com/TheUsefulLists/UsefulMods

You can try Java tweaks - https://github.com/brucethemoose/Minecraft-Performance-Flags-Benchmarks or performance mods - https://github.com/TheUsefulLists/UsefulMods

Reference this list of performance mods, find your version, and ensure you're using as many as possible (as long as 2 don't conflict.)

Just an FYI, that list has been archived and is no longer being maintained. Use this instead: https://github.com/TheUsefulLists/UsefulMods

I'm in no way an expert either, but let me firstly link to this Github page: ActuallyUsefulMods. It's a list of all the performance mods available.

i use a worse pc and I'm fine lol just use 6 to 5 gb ram allocated and add some performance mods https://github.com/Radplay/ActuallyUsefulMods click on the version you want and have a look its very useful have a nice time with mods

Also, here's a list of performance mods. Click the link for your version/loader and install some of those if you haven't already. If you decide to play on Forge, ModernFix is another massively helpful mod that isn't listed there.

Here's a list of all 1.16.5 performance mods: https://github.com/Radplay/ActuallyUsefulMods/blob/main/Performance/Performance116.md - I would highly recommend installing as many of these as possible. If you're using the OptiFine mod, get rid of it and use Rubidium instead.

Better performance mods - https://github.com/Radplay/ActuallyUsefulMods