Little FPS in Minecraft despite a good PC?

I have a good PC that performs very well in other games, but in Minecraft I only achieve 20-50fps high settings and low 80max my PC specs are R5 3600 RTX 2060 2x8GB Ram 3200mhz B550 motherboard does someone have a solution how I can change that. Because in other games, for example Fortnite, I manage 240+ FPS

Have you already assigned more ram to MC?

Chunks?

How much ram did you assign to MC?

Tp?

In addition: What resolution does he play with?

No TP, no shaders and no mods

1080p

Yes in total I have 6GB at Mc

9 chunks 6GB RAM and no Optifine

Yes

And every time I start Minecraft I have a black screen for about 5 seconds

That only happens to me in 1.16.5 in 1.8.9 I have up to 400fps but huge FPS drops

Then it will be due to the version?

by the way, what do you need so much fps for?