AY 19-20 44AD in ITR-3 & AY 20-21 44AB

Section. 44AD is applicable to Individuals, HUF and Partnerships firm only.

Turnover limit for 44AD is 2 crore.
if your Turnover is more than 2 crore than you can not file return under section 44AD.

To adopt 44AD you are required to file form ITR 4 , not ITR 3.

If Tax audit is applicable to you, than you can not show income under section. 44AD