Hey! to start off your best unit right now is Hashirama New Year so I'd put him in your team. Your goal for now should be to spend ninja points to 4* Choji Great Ninja War. Press on recruit -> top right corner to find the shop. Save items for rebates, that includes Cave Keys, Refines, Charms, Seal Scrolls, summon scrolls, and most importantly coupons. You should aim to either 4* Madara Edo Tensei Release or Naruto Sage of Six paths as they both have very strong breakthroughs.

However, if you have no emotional attachment to your current server I would start over on a brand-new server.
1. So you can be more competitive with your server mates

2. You get better rewards in the 7 day login nowadays, including 4* Choji great ninja war and 3* Madara Edo Tensei Release