You dont have any good pos 1 ninjas right now so I'd honestly just go with the main character. I'd suggest this team:

- Fire main pos 1 with the Mirror Return passive and the Unparalled passive combined should be as close to a debuff immune pos 1 ninja you can get right now. He also scales from Unparalled so that's good for pos 1.

- Ao is an underrated early-game support imo. He'll shield himself and Fire main at the start of the fight, gives some defense w/ clones that also give you chakra when they're destroyed, and he can acupuncture/interrupt round 1 and stop an opponent from putting up barriers or shields of their own. This is especially important if you don't have Hashirama's gold +1 breakthrough on his mystery.

- Ao also causes acupuncture on his chase, which triggers during the chases after Fire main's mystery. Causing acupuncture/chaos/immobile/interrupt on a chase is really nice to have if you can't cause one of those effects immediately with the mystery itself. Say you mystery before your opponent and their pos 1 ninja can't dodge, but they've already triggered their mystery. You will interrupt them with Ao's acupuncture (if you can chase) and they wont mystery.

- Most people seeing your ninjas would probably put Sage Naruto pos 1 but he's just going to get chaosed by Summer Kurenai or Rinnesasuke, or immobiled by Kurenai. That's why I put Fire main pos 1 since you are less likely to be controlled if you use the talents I showed. In this team Naruto is just providing some defense with his clone that will show up in front of Fire main and tank some of the "targets the front row" type attacks from the opponent. You should also be able to use both Fire main and Naruto's mysteries in round 2, assuming at least one of Ao's clones dies in round 1 and/or you get up Hashirama's barrier and he absorbs some chakra from the opponent.

- Hashirama. It's better if you have his breakthroughs but you probably don't have all of them yet. For future reference getting his mystery to +1 is the most important, because then it becomes prompt (instant). The second most important priority is his second passive, the Y form makes him immune to debuffs. But even if you don't have those BT, or any at all, he's still fine for this team. If you can get his barrier up it's a nice buff. Even if you don't, he still provides a great ninjutsu buff for the whole team, that's the biggest reason why I added him.

I hope this team works for you. In the long-term you can save coupons to buy some of the more exclusive, good pos 1 ninjas like Kimono Shisui, Edo Minato, etc. In the more short term, focus on getting your Edo Nagato 4* with breakthroughs by getting his frags from the redeem shop. He's a great free support. You c*so get GNW Choji frags, he's a good f2p early game ninja with his BT.