Or betas, critique partners. There are several names for the person that reads your work and offers constructive criticism. This person can be anyone. He or she doesn't have to be a writer and doesn't have to even be a reader. It just has to be someone who can offer an opinion. An aunt, a teacher, a best friend, or even someone you don't know that you met online (though you do have to be careful with the online beta readers sometimes). A beta reader takes your work, reads it, and tells you what they think. That's all. What needs work, what characters are inconsistent, etc.
But where to find them?
I'm going to mention a site that I've been on for years now, and I'm completely sincere when I say that being on it improved my writing drastically. Laina also mentioned it. The Young Writers Society. There are other sites to find beta readers, of course, but this is the one that worked best for me. I love it, and though I'm not browsing the forums or posting my work so much anymore, it still offers that platform for writers.
I realize this post is brief, but if anyone has more questions on this, just e-mail Y.A. Lit Six.