Row checker but only certain columns

I am looking to use VBA to do the following below with the goal of finding a cell that does not match other cells (image may explain better -- https://ibb.co/d2rtx5). I don't have anything written up that would help because frankly, I am not sure what to use to make it work.

Concatenate A and I into P
Compare P row 1 to P row 2
If same, ignore
If different:
does A1 = A2 ==> no, ignore
==> yes, find "COMP" in J (lets say found in J4)
Use same row and copy I4
does J4 = a1,
no ==> find "COMP" in J
repeat until yes then
Paste Copy into I1
Repeat each row

Then repeat but concatenate A and H and copy H4 (at this step: Use same row and copy I4​)

let me know if you have additional questions.


edit:
I tried to post my vba but it just says im attemping sql injection...


apparently this website meant to post this stuff cannot handle it being put in a post... you can get an image then: https://ibb.co/efGe4k

As you can see from the code, I am no where near what I need.