Can I use chap stick for instead of cork grease?

Only short term. Pick up some cork grease when you can, wipe off all the chapstick. Use it in your lips when you are not playing. Best lip stuff for us woodwind players is Chop Saver or the Nivea plain stuff - they bought out Lo Bello.

NO.

In an emergency, yes. I've used it to supplement the grease on my wooden Irish-style flute in a pinch, which uses cork and traditional hemp caulking.. I prefer LeBlanc Slide Ease for corks and brass tuning slides. Its a thick gel in a squeeze tube. BTW, never grease the joints of a metal flute, only corked joints and brass tuning sides.