Hey @BRIGITTE_BARIL!
I believe that by table you mean “base”, and by tabs you actually mean tables within the base :D!
Yes, you can have a linked field between the two tables. Link all records of Table A to a given record of Table B.
On Table B create a rollup, rolling up values from the linked record to Table A. Apply the SUM(values) formula in the rollup. That should be it!
Sorry for the lack of screenshots, I’m writing from my phone! Let me know if that somehow helps.
Mike, Consultant @ Automatic Nation