Improve performance

There are some ways to improve your performance past installation. Some of them are experimental and should only be used if you really want to.
Setting your allocated memory
Allocating more memory to Minecraft may increase performance greatly, but setting it too high can cause issues as well. If you have a low amount of memory installed, please make sure to keep enough memory for your system. As a general recommendation, 2-4 GB (2048-4096 MB) is usually all you should use for unchanged Adrenaline, Additive, or Vanilla. Playing with many mods? I'd suggest 3-6 GB (3074-6144 MB), however you may set this lower if needed. Do what works for you. Never set your allocated memory to the same amount as your installed memory.

If you are severely limited on memory, Adrenaline can run surprisingly well even with a minimum of 768 MB because of ModernFix and FerriteCore. Probably can be playable at even lower allocations, however I do not test with very low RAM so your mileage may vary.

In Prism Launcher, you can set your memory by going to Settings > Java > Maximum memory allocation. You may set the minimum memory too, however I haven't noticed any improvement over using the default.

Change your Minecraft settings

General

Start by changing your render distance. The higher this number, the further you can see. If you are playing on multiplayer, servers usually have a cap for render distance. On low-end systems, this should be set to 4-8 chunks. Mid-range systems will usually work well with 8-16 chunks, and high-end systems should be fine with 12-24 chunks.

After this, you can change your simulation distance. This is the distance in chunks that entities, blocks, fluids, etc are ticked, meaning that things like farms outside of this distance may not work properly. Unless you have areas with big farms and such, the default 5 should work well. If not, use 8-12. This only affects singleplayer - you won't notice anything while playing on servers as they have their own setting for simulation distance.

I recommend keeping V-Sync turned off unless you notice screen tearing, which in that case, turn it on or use Adaptive V-Sync. To use Adaptive V-Sync, you will need to install the Sodium Extra. If you are using Additive, this mod is already included. Adaptive V-Sync typically has less input latency than normal V-Sync.

Quality

Set graphics quality to "fast" on low-end systems and "fancy" on mid-range to high-end systems. This will affect if leaves are transparent or not, weather particles, and other things. **Do not use Fabulous unless you absolutely need it's benefits, as it can have a noticeably negative impact on performance.
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Set particles to "minimal"/"decreased" on low-end systems, and "all" on other systems. For greater control over particles, install Sodium Extra.

Optimized Java runtime and JVM flags (advanced)

Warning This part is generally meant for advanced users! If you don't understand how to do this, then you should ignore this and stick with what you have now. I will not offer support for setting this up.

Tuning the JVM can be a good way to improve performance for some people, especially server-side. Follow along with this page for some more information about this