Need help with protection

Tagged as other because i have no fluffy idea what to tag it as.

Recenyly, my grandmother got possessed by a spirit of another religion, that claimed he was targeting me. My family does have history of possession from that religion. I, as a Hellenist, am shit scared. But i needed help. I thought of summoning a God, any one, that could protect me. I immediately thought of Ares, the God of courage and war. If there's anything other than summoning i could do, you can tell me, please. Otherwise, i need to learn how to summon gods, and which i should.

For now, i have a huge, round, red, spiritual target painted on my back.