I am from bihar .I am in obc category .I got 44 in maths 63 in phy .62 in chemistry in my board exam . Am I eligible for wbjee .

According to the eligibility criteria of WBJEE for reserved category students, candidates need to have scored a minimum aggregate of 40% in PCM/B in 10+2 qualifying examination. Based on the data you provided, your percentage is around 57% (PCM aggregate). But, there's also a domicile criteria which states that candidate should be a resident of West Bengal for 10 years consecutively or the parents of the candidate must have a domicile of West Bengal with a permanent residential address in the state. So, if you have a domicile of West Bengal you'll be eligible for WBJEE. If not, sadly you won't be eligible despite having secured enough marks.
Hope this helps. Good luck.