Brexit-supporting MPs, including Suella Fernandes, chair of the Tory’s European Research Group, asked for assurance the bill would not be used to reverse Brexit. Davis said it would be a meaningful vote but that it would not undo the process.
When Owen Paterson asked if the UK would still leave the EU in March 2019, Davis simply replied: “Yes”.
The list is basically neverending, but essentially all deals between the UK (trade, customs, rights of residents, mobility, visitation, marriage recognition, health care reciprocity, transportation, and on and on and on and on) and the EU are deals that exist within the framework of the EU, so "no deal" means...no agreements. Literally all gone. Ripped up at 11PM London time on March 19, 2019. Some things default to WTO agreements, but they don't cover everything.
In addition, a lot of UK deals with the rest of the world also operate through the EU framework, so all of those agreements get ripped up. They can't sign new ones until Big Ben strikes 11 (and Big Ben currently isn't even bonging). Sure in theory those deals can be inked and signed at 11:01, but in practice things don't quite work that way, and they're going to be a bit more important for the UK than other countries. Influential interests, right or wrong, in every other country will want those deals to favor them more than they do now, and expecting any government to be a model of speed and efficiency for this stuff is lunacy.
Just as a small example: UK airline carriers wouldn't have the right to land in the EU. They wouldn't even have the right to land in the US!