Me and a friend have already created 2 worlds and every time the world gets a little bigger everything runs slower and jerky. However, this is not the case with new worlds. When I sent the world to him and it was directly on his laptop and not on mine, it wasn't any better. We both have the Windows 10 version.
Best to put down chunks
In this case the CPU is too weak when calculating the chunks. Putting them down should help.
Do you play on a server? If so, expand the Ram at Nitrado.
What settings do you have? Do you play on a server? If so, how much ram does he have? Is your internet good? Windows 10 is actually not so good in my opinion but ok. What about shaders and TPs?
The solution was both sad and funny. It was because we kept a lot (hundreds) of chickens on one block. When we killed them everything worked perfectly.
