If i share carmex/lip balm with someone who has hsv2 will i get it too?

Probably no risk. Oral infection with HSV2 is uncommon, so that person probably could not have contaminated the product. Still, it is dumb (and gross!) to share such personal products, risking colds, flu, covid, etc. And Carmex or lip balms cannot treat or prevent any infection anyway, so no need to use the stuff. If you really want to use it, buy your own!