My WBJEE rank is 48102 and JEE Mains rank is 603000. Can I get admission in a government college for engineering?

Your JEE rank is not decent. With this rank its hard to get any good college. What I would suggest you is to try for good private college if you are okay with the fees or else try next year with hardwork and if you trust yourself that you can crack it next time. Don't lose hope. Good luck.

You must have to score minimum of 20000 rank to get into any government college. In JEE Mains. Without qualifying JEE, you can't get any government college.