Both are the same level colleges in term of Placement, Faculty, Student crowd, Infrastructure etc. You can choose as per your convenience.  Companies like Tata, Infosys, tcs, amazon, flipkart and other important companies coming here for every year in GCE, GAYA. You can check the all about detail of Bakhtiyarpur college of engineering with the given below link.

https://bcebakhtiyarpur.org/

You can check the genuine reviews of the colleges with the give below links.

https://engineering.careers360.com/colleges/gaya-college-of-engineering-gaya

https://engineering.careers360.com/colleges/bakhtiyarpur-college-of-engineering-patna/review

Good Luck!