Query regarding revised income tax return

Assessee is having salary income plus business income and he already filed original income tax return for the assessment year 2019-20 but erred in showing income under business head.

Now he will have to file revised return for correct income.

Can he show income under head business u/s. 44AD in revised return ?

Whether there is any chance of receiving notice from i t dept. for showing additional income in revised return of income ?

Please do the needful in matter and oblige.