Yes upload all your invoices (sale) in respective table of GSTR1 of Feb 19 Means Jan & Feb 19 data consolidated & reported in Feb 19
Thanks for your answer.
I think the relevant section is export -6A since I provide online advertising services to overseas clients.
So I just add the invoice no, date, invoice value and taxable value. My another question is - Should invoice & taxable value be same since I can't charge GST from overseas clients? Please note that I also applied for LUT in order to file return without payment of taxes.