How long will fake nails last if they're applied with nail polish?

So, I don't want anything harmful on my nails that'll put me at risk of possibly taking off my actual natural nail which I know will only happen if the nail isn't taken off properly. But, I don't want to deal with acetone to remove it (kind of freaks me out when it's just sitting in my house when I'm not using it cause it's highly flammable and ruins/melts everything it gets in contact with, so I never bought it again). I don't want to use glue either cause this will be on temporarily. I wanna use nail polish since I heard it works. If I was to use nail polish, how long would it last? Like an estimate on the number of days...please tell me! Thanks! :)