I want to make a cell equal to the cell above it.
When I write
=address(row()-1;column())
It just writes the name of the cell above(for example for B2 it writes $B$1)
Is there a function which inputs the address and puts the value?
Try using the OFFSET function to offset the cell by -1 row. For example you can paste the below formula into cell A2 and it will return the value of A1:
=OFFSET(A2,-1,0)
If, however, you really want to keep your present address method, put it inside of the INDIRECT function like this:
=INDIRECT(ADDRESS(ROW()-1,COLUMN()))