my boy wishing i would let him ride it

I am a new atv owner...I bought a used atv this summer (pretty sure it is a wolverine but reg card from last owner didnt actually say that so idk for sure). It ran great for most the summer and early fall but one day I tried starting it and it turned over a while without starting and then suddenly it quit turning over at all. No click or anything.
I charged battery and light turns on showing neutral and heatlight can go on.
A few other things that may be pertinent: The pull start is missing, I have a fluke multimeter but not many other advanced tools (or relevant experience), there is an extra aftermarket led light attached to front but it doesnt work either... never looked into why since I didnt need it. 
I looked for a fuse box and didnt find one.
Please recommend some easier things to try first as I really want to avoid taking it in if I can (having one income and 4 kids can keep out extra cash, plus I want to learn). Pictures would be awesome if possible. Thanks! 

I have recently rebuilt my Yamaha warrior 350 engine and when I got it all back together with no “spare parts” i went to start it and realized it’s in reverse. I went to put it in drive and the shifter won’t budge, I took the linkage off and tried to use vise grips but it won’t budge at all. Any help would be greatly appreciated. I’m hoping it’s not something internal! 

I have a Yamaha Big Bear 350 and the reverse doesn’t work, it shifts from low to high easily but it won’t go back to reverse. I’m new to this stuff, so I’ll take any help. Any ideas? 

Where can I find a wiring diagram for my 2005 450 Kodiak. Thanks.

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