Is it a good option to pursue BE from an average college? Can I get admission in good government college? Should I change my field?

Since you haven't scored well in JEE mains so you will not get admission in Government institutes.Although there are private institutions that are doing equally good as them,you may get admission in them by scoring a good rank in their entrance examination and thereafter getting high scholarship.som

wait for other results also and always go with ur interest.