Can you get braces with a extra tooth behind big tooth?

Yes: In most cases yes, check with your orthodontist. Sometimes the "extra" tooth has to be extracted but you will only know for sure after being evaluated.

Yes, but...: A trained orthodontist can achieve amazing results. It's quite common to see very crowded or crooked teeth eventually guided into a ideal or near ideal occlusion (bite). Sometimes one or more teeth need to be extracted in order to achieve those results. You have to invest the time and finances and follow directions given to you. Have a consult to discuss your options and what it involves.

Yes+: I am assuming that you have one of your front teeth that is caught behind your two main front (central incisor) teeth. That would indicate severe dental crowding. Seek an opinion with your orthodontic specialist about how best to handle this issue, but definitely braces would like be involved in correcting your problem.