Just reading up on the deal, here are a few paragraphs I found.

At that point, Britain will leave the European Union’s single market and customs union, severing the economic integration with the bloc forged in recent decades as part of a huge trading area. Britain formally quit the bloc’s political structures in January but opted to remain under its economic rules until the end of the year, pending a trade agreement.

Critics note that Mr. Johnson’s deal secures little for Britain’s important services sector and means added bureaucracy for British businesses exporting to continental Europe that will have to make millions of additional customs declarations.

What this means basically is the UK is untangling itself from the bureaucracy of the EU but in return said EU has no tarif trading with Britain in return. I don't know if they'll have to give up their seat in the EU parliament but there's supposedly another bill after this one where they hash out those details. What this means is not a lot in the future I think. But come a crash in the Euro or another European country suffers a black hole in it's budget that needs to be fed with German bank loans it can't pay back, Britain is under no obligation to help them anymore.