How to delete itr saved draft

No need to delete that file. As ITR 2 cannot be filed online, just prepare X M L file offline and upload. That will nullify the said ITR1 saved draft.

What to do in case need to file ITR 4 while draft was saved as ITR 1, in this case how to delete draft ITR 1

I have saved my ITR1 for AY202021. I came to know now, that I need to fill ITR2 as I have some STCG from MF. 

Please tell me how to delete ITR1 and fill the ITR2 ONLINE ( not offline ).

Instead, you can start fresh by filling out the form again and saving it.