have you done your daily exercises?
dont let the nervousness get to your head. realize that they know you’re likely nervous, esp since your resume is probably pretty bare, and that they will expect some of your responses to be shaky due to your nervousness.
“tell me about yourself” is actually just a litmus test question meant mostly to break the ice - how do you introduce yourself to strangers, what kind of impression do you give off. focus on being professional rather than complete in your answer - it can be as short as a sentence or two if you dont have much relevant info to share.
starting off with facts like your name, age, current education status, and maybe one or two long term goals (may or may not be relevant to job) is a good generic short answer if you’re unsure what to say.
you can google common interview questions and their goals/purpose. this interview isn’t everything, they’re probably not expecting a perfect interviewer, so don’t sweat it too much if you stumble a bit.