Looks like there are a lot of options for you
https://www.bonus.com/indiana/sports-betting/
It is typically pretty easy to get started, with a simple transfer from a bank account to your sports betting account. However, I would look into a few things to decide which site to use.
1. How difficult is it to get your money back out? My first account was with BetDSI and I would never recommend them because they will milk you dry trying to actually get your winnings.
2. Sign up bonus' (which that link above compares)
3. Do they cover all the sports/organizations you would want to bet on?
4. Prop availability (FanDuel is available in your state, and their UFC props are great)
5. Overall odds. Some sites take more "juice" or "vig". The closer their negative numbers are to the positive number, the better. For example, on
www.bestfightodds.com you will see that right now draftkings is -155 Poirer, +135 Oliveira, whereas BetMGM is -165/+135. This means BetMGM is taking more money for the house on this particular matchup.
I would be happy to answer any questions you have in PM if you want. The mods would probably rather I keep most of this discussion for the betting forums