How to work with pointers and offsets?

[E1M1]

Hello

I have played bit with memory reading and fount that pointer and offset isn't just as easy as I thought. Pointer is 6FBCB980 and ofset is 1b. How do I put these together?

If I use Chat Engine, I click "add address manually" and then for "Pointer" I enter "6FBCB980" and for offset I enter "1B" and then it leads to "0018F993". But when I try Hex(0x6FBCB980 + 0x1B) which returns me 6FBCB99B with offset 0 then it returned me diferent address than with pointer 6FBCB980 and offset 1B. So now I know that I can't just sum pointer and offset together.

How do I deal with pointer and in autoit?

I have something like:

local $pBuffer = DllStructCreate("ptr")
$iRead = 4
_WinAPI_ReadProcessMemory($call[0], 0xAddress, DllStructGetPtr($pBuffer),  DllStructGetSize($pBuffer),$iRead)

in DllStructCreate I use currently ptr. Is this right to use?

if Pointer is 6FBCB980 and offset is 1B then what must instead of 0xAddress?