My question is if you allocate more ram for minecraft has more fps ingame?
If you press f3 in minecraft, you should see in the top right corner how much of the allocated RAM minecraft is using, if that is almost 100% it can be good, but if you play without mods it is more the processor that makes up the fps
The FPS have nothing to do with the ram.
The FPS depend on the graphics card and your settings.