Hi Daphne,
Sorry I couldn't respond sooner, I have a major project going on at the house, and I didn't even see my computer till late last night.
I understand the frustration, but this should help you out...
Most times, getting to reverse involves first gear. So, pull in the clutch lever, shift into first gear, then turn, push, or pull the reverse knob. While holding it in position, shift down into reverse, release the knob or lever, and slowly release the clutch, while giving it some gas.
Most of the reverse systems require that you start from first gear. Honda has played around with their reverse system a couple of times, so if the above doesn't work, try the same process, starting with the ATV in neutral.
As for the battery, most auto/cycle parts stores will do a battery test for free. Simply take the battery into the store, and they will conduct a "load test", this will tell you if the battery is shot, or simply needs a trickle charge to work correctly.
The battery should not have anything to do with reverse, getting into reverse is a mechanical process, not an electrical one...
If you plan on keeping your TRX350, you might want to get a repair manual for it. You can find a the manual for your ATV here....
Honda TRX350 Manual
Should you find you need any parts, please check out our vendors, they are in the box at the top of the page.
Thanks for visiting the site, if you have any other questions, feel free to post them here.
Have a great day, Daphne...
Ride Safe. Ride Legal. Ride Again...Curtis