HELP! I can't get started!

[jonaequeen]

so I bought my first bike, a 2008 GZ250 for $800. the man I bought it from used it for his wife to practice riding. he told me he think it needs a new battery. when I picked it up it started right up with a jump. it was raining and I stopped to look at my directions home and I could not get the bike engine to turn over. I went and bought a new battery, put it in and rode about 15 minutes but made a new rider mistake and stalled. the engine wouldn't turn over again. I tried to jump it and it started smoking from under the seat so I gave up. I parked it for a few days until I figured out how to get it home (it was raining a couple of those days). I finally get it home, get a brand new battery bc I think I fried the other one and NOTHING, not lights no power at all. I could really use some insight as I'm no where near a mechanic but with knowledge and guidance from you all I think I can get it done and get it going! thank you in advance

UPDATE: The main fuse was blown. I replaced it and now i have power! However, the bike still won’t start /:

[Vegas Street Rider]

My biggest concern would be why the new battery got fried. You may have a bare wire going directly to ground or rain water got into a vulnerable spot. Check the wiring harness for damage and repair as needed. Check continuity through all your switches (cut-off switch, kick-stand switch, clutch switch, etc.). I would also check continuity through the harness plug in your headlight can and check for water. Electrical issues can be hard to track down. Check to make sure you have spark at the plug as well.

Others will come on the forum eventually and may have additional info on things to look at. Be patient and good luck.

[5th_bike]

The wires that run under the tank and above the head, sometimes get their insulation melted off by the hot engine head, and then you get a short. My bike had that when I bought it. Took a couple blown fuses before I had it figured out.
The tank is easy to get off, but be careful, there are two rubber hoses at the petcock - the fuel hose, and a vacuum hose to the carburetor. You can leave the petcock ON, and only the fuel from the fuel hose will spill out.