Hello
I am afraid your question is not giving a lot of context here -
Are you setting up the computer out of box brand new?
Or are you currently using an account that doesn't give you admin access? If that's the case, do you know, does the computer have another admin you don't know the credential of, or you are the only user on the computer but you don't have admin?
Once I know what the context is, I will have a better idea what your options can be.