Gst adjustment possible ???

Yes. You can adjust your ITC to the following way,

IGST = 1. IGST 2. CGST and 3. SGST

CGST = 1. CGST and 2. IGST   (Not available adjustment CGST to SGST)

SGST = 1. SGST and 2. IGST   (Not available adjustment SGST to CGST)

Also you get refund if you have any Input Tax...

In Vat resime we fill return first then pay tax .

In gst resime we have to follow the same procedure ??

or we have to pay tax before filling the return ?? 

It's your choice....

It's your choice....