@Katelyn76 It kinda works the other way around- no one wants to hire someone as a co-host so they can gain experience, unless it's close friend or family member. Usually people have either hosted themselves, or worked in the hospitality industry when they take on a co-hosting job.
Maybe I'm misunderstanding, but it sounds like you expect to be paid to be trained. If you have done things like this before, mentioning what your experience is would be what hosts would want to know.