Ex: =A1+A2 next cell down A3+A4 next cell down A5+A6, not A1+A2, A2+A3, A3+A4. I am trying to net cells, some are exact duplicates, some are not
If the formula have some patterns (as per to your example =A1+A2, and then =A3+A4), then yes it is possible.
If you put (for example on B1) = A1+A2
highlight both B1 and B2, and then click and drag the bottom right corner of B2 (it should show as a thicker box) and drag and it will follow the pattern you have set previously.
If this is not to your need, you will need to update your questions with more details, and preferably some examples.
If you are just trying to solve the A1+A2, A3+A4, A5+A6 problem, here’s a solution: Enter
A somewhat more general approach would be
which explicitly references the two cells separately.