If someone gave me a bike as you describe, I'd forget about riding it for a while. It is easy to rush the ride and ruin an old bike. Take a month or two as necessary to make the bike road-worthy. Do not spend any more money than necessary until proper performance is proven. Hence:
1) Pull the battery, fill with distilled water, and charge. Probably won't be any good, but you might get lucky;
2) Get a park plug to keep cooties out of the combustion chamber. Stick a shop vac hose over the plug hole and kick the engine over slowly a couple times with the kick starter. Pour a teaspoon of engine oil in the plug hole, turn the engine over slowly several times, then use the electric starter (either with the old battery, kicker, or using 10-gauge jumper wires) to check that the plug actually sparks;
2) Give the bike a good detailing and going over looking for anything rotted, rusted, or loose, though I would not as yet spring for replacement tires and tubes;
3) Do a complete tune, service, and adjustment check on the engine and chassis, including lubing all parts listed in the manual with the specified products or equivalent, and use engine oil blended specifically for 4-stroke motorcycles with wet clutches and filter (I'd use a less expensive dino oil at first, then change it after a few miles);
4) While the fuel tank is off for service, drain, rinse with kerosene, and check the petcock for proper function. While the tank is off, replace all the rubber hoses--they are cheap. Install an inline fuel filter if there is rust in the tank. Fill with fresh gasoline, preferably without ethanol if available. Add Seafoam;
5) Put it all back together
6) Air the tires.
7) See if she'll fire up.
A) If so, putter around the yard a bit to check for proper operation of all mechanical components. You might get lucky with the carb, especially if the carb was drained before the bike was parked.
If no, check for spark before delving into the carb. If you have to go into the carb you'll probably find it necessary to replace the rubber duct to the air filter due to shrinkage, and might as well check the float level and rejet while it is apart. Go ahead and save yourself the trouble of doing it right the second time and do it right the first time--disassemble, inspect, order replacements for any iffy parts, reassemble, reinstall, and tune.
8) While waiting for the carb parts, address the electrical issues. Maybe the turn light is only a bulb. Maybe a wire unplugged.
9) Once the proper operation of the bike is proven, move on to the more expensive maintenance and repair items, such as battery and tires and tubes.