Formulas and Multiple Columns

We are making the slow move to for some of our project financial tracking. Our 'Check column in Excel helps us make sure that the anticipated future billing aligns to the remaining fee (formula is =SUM(H2,K2:AA2)). If it matches Phase Total, all is green. If these columns are out of sync, one will turn red.
Is there a way for’s formulas to sum columns similarly? I also looked at the conditional formatting on the Board and it doesn’t appear that I can set it to if Column A =/= Column B, do X.