A a friend of mine said he could recommend me to a junior DevOps role at the company he works in, but I'm interested mostly in back-end development and DevOps is not really something I like. The question is: could I use experience as a DevOps to later switch to back-end?
Edit: more detail
In most companies, most of what a devops "role" does would be handled by backend devs anyway. Plenty of crossover between a devops role and a backend dev role. The important thing is to get some work experience anywhere in development to make yourself look way more appealing in future job applications.
It depends if it's a real DevOps role, or an operations role with a DevOps title because it's trendy. In the former case, the role should include some kind of backend development.
Devops is a nice skill to have for a backend developer, however I'm not sure it is fair on your friend if you take a role you don't really want and might not perform well in.