I am trying to convert the cell reference in the formula1 from a specific
cell to a program selected cell;

B391 to cells(rowindex,columnindex)

(actual code)
Range("B996:Y998").Select
Selection.FormatConditions.Delete
Selection.FormatConditions.Add Type:=xlExpression,
Formula1:="=AND(B391=1)"

everything I try turns into an error

Selection.FormatConditions(1).Interior.Pattern = xlGrid