Friend i got 79 and opted only for main campus but haven't alloted seat 

Have u got alloted seat after councelling

hello, 
yes you can get the admission in BHU if you have scored 70th rank. 

refer to the link below for cut off list

https://university.careers360.com/articles/bhu-pet-cut-off 

for gen, cut off rank being 631 and cut off marks 80.