Working at a tobacconist???

Keeping this vague as I don’t want to get in any trouble etc but, I’ve been job hunting for months with no luck and put my resume into the tobacconist thinking nothing would come from it. Well they’ve called me in for a trial shift. I’m desperate for work but unsure of whether this is a good idea. If the tobacconist is selling vapes and chop chop can I be held liable if I don’t own the place and just work there? The place in question has never been raided or anything as far as I am aware and seems just like any other tobacconist (there’s approx 3 others on the same street). Idk just give me any input you’ve got, anything I should ask the owners on the day?