Mmu | How to set different virtual address than physical

Hi, in my current understanding, when I want to map a certain range of virtual addresses, for example 0xffff-0xffff8000, to 0x0-0x8000, I have to put the physical address in the section entry (0x0-0x8000). Now if I want to map 0xffff-0xffff8000 to 0x800-0x10000, the adresses in the section entry are 0x800-0x10000,

is that correct? Bc I have the exact same setup and although the section entry(the last block entry that points at the physical mem)  address is different than then the virtual it’s address it still points to an range beginning at 0, so with zero offset…

What do I have to do to have the virtual address point to another(with an offset, of that makes sens) physical address.

Sorry, I find it really difficult to explain the problem at hand.

Best regards Niklas