Interested in plumbing but

I'm interested in plumbing and moving to Colorado to do it but I'm someone who uses THC to manage anxiety since I don't like what antidepressants do to me and I hate alcohol. I mostly want to know if there's any companies in Colorado that will hire you if you use THC since it's s legal substance in Colorado and I kind of view it like drinking a beer after work. Are there any states other than Colorado where THC is legal and it's illegal to fire you for failing for THC? I want to be able to make a living doing this job and I'm willing to give it up for a career but I just think it's dumb that other people can do it when they're off work but if I do it I'm out of a job.