Which brokers offer nanos?

topstep brokerage is the cheapest I've found, but be aware that if you are going for 20 to 30 point wins this is going to be very hard to be profitable for you.. I have caught lots of 50 to 100 pt moves, a couple 150 and one 250 point move.. with 1 or 2 nanos.. it really doesn't add up in the long run, and I eat through all the profit on barely profitable trades, losing trades really hurt because you take the loss AND pay the fees.

Almost all of them. Amp, TradeStation, NinjaTrader, IronBeam, Webull, etc.

For staring out with futures in general, you should use ninjatrader. Their web-based platform isn't as advanced as other platforms so it's easier to figure out how things work. Then you could move to more advanced platforms later. I'm not sure if many people trade nanos due to the high fees but I would recommend paper trading first and then going to micros for live trading.