GTA and E invoice

Anshuman Basu (account -GST) (1549 Points)

15 March 2021  
Dear sir/madam

We are Registered GTA having 8 Branch in eight state. our previous year 19-20 turnover is 145cr, Now in 20-21 turnover will 200cr.
My Question is, E-invoicing is applicable for us?
If Applicable the What is the GSTR1 and GSTr3B filling procedure?
The 2nd Question is what is the latest Change of GTA service?

Anshuman Basu