Hello, all.
I work in the health care field and i'm trying to use excel to track patients and injection intervals plus inventory to order medications.
I have a worksheet in progress
here is my question:

I have several cells with a dates. The cell to the right of these i want to place a formula that will calculate the next interval date of one week, two weeks, three weeks or four weeks when inventory and injections will be due. I want the cell to the right to auto calculate the next interval from the date entered in the cell to the left of it.
Does anyone know if there is a built in formula for this or know how to structure a formula for this

also i want to share this sheet with several colleges on different computers , so changes can be made and all and dates/changes can be seen when entered.
Basically a live spread sheet that can be used by multiply people.