Here is what I was looking for

Suppose Cell B1= 2 , then I wanted to cells C1 and D1 to be blank and
locked ( Locked in the sence, no one should be able to write in those
cell. They should be as good as merged cell where I can't even blink my
cursor)

So depending on the values of the cell in column B, I wanted to make
the equivalenmt cells in that row as dead locked.
Suppose B1 = 3 then C1 D1 and E1 should be dead locked.
Suppose B2 = 4 then C2, D2, E2 and F2 should be dead locked.

Dead locked means no one should be able to write in nor format those
cell.