I have put in new ignition switch and a new battery.Nothing, won't turn over and I know nothing about engines.What can I try next to check.. Also does the bolts on the new battery need to be special ones.I lost the ones when removing so used bolts I had it.They fit right? I know I am a dumb blonde... but can someone help.

Any bolt that fits works,, did you try checking the solonoid, did you check starter to see if it works,, check starter directly by placing ground wire on starter body and the positive on the bolt that the large wire is attached,, if starter turns engine then the starter is OK, and again try checking the solonoid,is the switch the same kind and same number of wires,, there should be a wire from switch to the solonoid

Since you said you just bought the mower I thought I'd make sure you know a couple things. There are safety switches on these mowers. For most riding mowers to start the deck has to be all the way up, the blade engaging handle has to be in the released position, you need to be sitting on the seat and the brake/clutch pedal has to be all the way down. All of these things have switches to make sure that they are accomplished. If any of those switches are not working properly it will not start.