What is the difference between gstr and gstrb ?
GSTR-2 is a monthly tax return showing the purchases you've made for that month. When you make purchases from registered vendors, the information from their sales returns (GSTR-1) will be available and autopopulate in the GSTIN portal as GSTR-2A for you to use in your GSTR-2
GSTR-3B is a self-declared summary GST return filed every month Taxpayers need to report the summary figures of sales, ITC claimed, and net tax payable in GSTR-3B. A separate GSTR-3B must be filed for every GSTIN