opjose gave you very good advice.....the local field and an instructor is the way to go.....Even a small airplane transported on a bike is a risk to you and your plane.
I just can't recommend flying in any baseball or soccer field....Your airplane once seen will be a magnet for people to come and watch....trouble is there are too many dumb masses that will want to get too close and impeded your landing...after all you'll be watching your plane.
I do agree that 4 channel is the way to go...but the bigger the better....a small light airplane will be blown about more than a biggger aircraft.
There are alot of good 4 channel glow powered trainers on the market.
I am assuming you're younger, don't drive yet, talk this over with your folks. This is a wonderful hobby....if your local club has a club trainer, you maybe able to start your lesson on their trainer.
Good Luck