Those things arent to easy to work with. Get or find some info on diasssembly.but if you dont have specs on part tolerances its useless and a waste of time.
you can do more damage than good.
if you want to get some dieasl fuel and pour some into the cylinder if you think its stuck. through spark plug hole
this can only work if the piston is covering the exhaust port.
let it sti for a few days (top upevery day) remove the head and using a peice of wood(peices of broom handles) and hammer, wack the wood so that it hits the center of the piston. the piston should move and be free after 3-4 hits(good ones)
see how smooth the cylinder is if it has a small high spot use 2000 grit and be -Very careful-light and slow (think of how to catch the metal dust so the dont get to the rings)
i wouldnt go any further than that without a manual.
Thier should be a way to turn over the motor without the kick to see if its seazed