How do i put the kickstart on a 1995 yz 80 - yZ 85LW Yamaha Motorcycles

I'm assuming you mean gas comes out the spark plug hole with the plug removed??? You probably have a gummed up carburator, due to old gas or dirt. Make sure your air filter is clean first, and then get your carburator thoroughly cleaned. If your float is sticking, or the float needle is dirty or worn out, it will keep dumping fuel to the engine.

hi , two things to look at : 1- change your oil to a not so thick oil which could cause your problem . 2- your clutch could be too tight therefore needs to be relaxed to allow your kick start working

Sounds like the piston seized.
Pull the spark plug and hand crank the engine if the piston moves up and down with little effort your ok but if you have a lot of resistance top end rebuild needed.

Common cause of kickstarter not engaging(I am guesing that this is your problem) is a broken spring on the kickstart mechanism,or that the kickstart idler gear cerclip has fallen off(this allows the idler gear to move forward on the shaft & thus won't allow the kickstart gear to transfer drive to the clutch hub).Remove clutch cover, put kickstart lever back on shaft spline,activate kickstart lever by hand(easier with sparkplug removed+in neautral)as kickstart lever moves down 90 degrees the gear on the kickstarter mechanism should move out to engage with gear next to it(kickstart idler gear).If the gear on the kickstarter mechanism dosn't move outward it has a broken spring on the kickstart mechanism.replace spring and all should work.(if the spring is broken you need to try find the broken piece with a magnetic pick-up tool as the broken part can cause further damage if not removed)To do this job I highly recommend you first purchase a workshop manual which will guide you through these processes.After all a manual is the most valuable tool in your tool kit.

CHEK TOP OF ENGEN NEAR KICKSTART THERE SHOULD BE A NOB TURN IT LOOSE AND PULL IT OUT YOU SHOULD SEE A DIPSTICK WIPE CLEAN AND REPLACE TAKE OUT AGAIN LOOK AT MARK ON DIPSTICK FOR OIL LEVEL IF LOW ADD OIL TO THE MARK ON DIPSTICK