thank you, here is how I did, now seems all messed up

sipsorcery:
sip account: my account owner/name (the same) and ps, domain is sipsorcery.com. both in/out dial plan are empty. Standard is picked

sip provider: input everything to the right spots according to sipgate confidentials.Server: sip:sipgate.com. Register contacts: sip:*****@sipsorcery.com.

Dial plan is empty now after trying to set up in/out plan, it used to be "default"

my ATA (SPA3012): on line 1, simply set to connect sipsorcery.com as proxy, outbound proxy is empty, GW1 set to [e-mail].