hii Amarjeet

Yes , you are eligible for the bhu UET exam in 2020.

MINIMUM ELIGIBILITY REQUIREMENTS: Passed 10+2 or equivalent Examination securing a minimum of 50% marks in the aggregate in the subjects Physics, Maths plus any one of the following: Chemistry, Statistics, Geology, Computer Science, Informatics practices and Geography and must have passed in each of the concerned three subjects. 

You can fill form from BHU website in 2020. UET examination organise for undergraduate courses. 

      Hope I resolved your query.