Hi there have a problem with a tenant who s rent is in arrears his contract has ended so should be paying monthly has missed last 2 payments can he be evicted immediately or does section 21 need to be served then 2 months from there help

In what state is the property located?

Generally you can give him a 3-10 day pay or quit notice (depending on where you are). If he pays he gets to stay. If the 3-10 days expire without payment or vacating you can file for an eviction order.

Or, you can give him one rental period's notice that you are terminating tenancy, and if he doesn't comply, get an eviction notice.