How many players can my server handle?

So I’m developing a server for 1.18 when it releases. I have 8gb ram on an i9-9900k cpu with a NVMe SSD and about 15 plugins.

Essentials
Vault
EconomyShopGUI
Silk Spawners
LuckPerms
World Edit and Guard
Enjin
Spartan
Chunky
Citizens

I will be pre generating the world along with other optimisations, how many players you think I can handle?

Could be 8, could be 80. It depends on a lot more than just what you listed. You kinda just need to try it and see.