During this transition period virtually nothing will change for businesses or for the public. The current rules on trade, travel, and business for the UK and EU will continue to apply.
The transition period will end on 31 December 2020.
It cannot be extended beyond that date, as the UK and the EU had until 1 July 2020 to agree on a possible extension.
The UK and EU will negotiate additional arrangements during the transition period.
In January 2021 a new relationship with the EU will begin.
There will be changes after the transition period ends, whether or not an agreement is reached on the new relationship between the UK and the EU.
More information from the UK government on the transition period is available at this link:
The NI Protocol
The Withdrawal Agreement includes a protocol on Northern Ireland.
It outlines the relationship Northern Ireland will have with the EU at the end of transition period to avoid a hard border between Northern Ireland and the Republic of Ireland.
Some details have yet to be decided by the UK and the EU.
More information from the UK government on the NI Protocol is available at these links: