If you are asking about how to check the oil without a dipstick:
On my 87 Kawasaki 305, to check the oil, you look through a little clear window on the side of the engine. Put the bike on its center stand or balance it by hand and the oil level should be in the center of the little window.
Well the KE100 is a 2 stroke. It should be oil injected and you would use 2 stroke oil. There is probably some oil in the case to lube the transmission. A stop by a kawi dealer out to get the info you need to change/check it.