Bohra and sunni marriage

I am a sunni girl and my parents want me to marry a sulemani bohra boy. I am literally very confused whether they are muslims,will the marriage be valid. Although they said that I can practice sunnism after marriage and nikah will happen in our masjid but still I am very much in a dilemma not understanding what to do. I don't have clear understanding on whether the nikah will be valid or not? Please if you could answer would help me a lot as my parents, especially my father are keen on marrying Bohra boy.Pls help.