It can be overwhelming at first for new players to SMITE in general, but just pick a god that looks cool and jump right in. Don't put too much pressure on yourself to learn everything as soon as possible!
Once you get comfortable and feel like really diving in, I recommend looking for YouTube guides/gameplay. There are loads of great players/creators in the community who make awesome videos, so be on the lookout for those. When I wanted to get better at SMITE, I would watch hours on hours of pros playing, then jump in game after and try to emulate things.
GLHF!
