IGST or CGST & SGST Under Reverse charge mechanism

I am a agent of foreign company who supply chemical in India.
I live in Kanpur, Buyer of chemical is in Kanpur, Supplier of Chemical is in foreign.
Company pay me commission on each transaction which is done through me.
Now Query is whether i pay IGST or CGST and SGST under reverse charge mechanism?
Also i Generate Debit Note in favour of foreign company.