I have a question about the transmitter. How do you know when to change batteries. Will controls quit or power or what. Should I change them every so much flying time. Thanks

I take it you plan on teaching yourself to fly? Please go to your local club and ask questions. Perhaps get in a flight or two or better yet learn to fly there.
Im not sure what transmitter you have, I assume it has double a batteries instead of a rechargeable battery pack.

Yes controls will quit when the batteries get to low. There is no practical way to have much warning with the cheap radios that use individual single cell alkaline batteries. Some may have lights or a simple meter but still that is not all that practical and not much warning.

I do avoid radios systems that do not use rechargeable packs with one exception I do keep a single Attack transmitter to buddy box fellows who have those systems. I tend to avoid problems simply by replacing the batteries often. It gets expensive.

Now on the positive side the batteries can last for weeks or days, it all depends on you. And you do not have to recharge every single trip to fly like you would with NIMH or NICD which are the most common rechargeable packs used in most Tx.

John