can I work two jobs then drop one when 1 when preferred one is ready?

Been looking for a job for two months now and finally found and been accepted for two.

One is working airport security and the second is a cleaner for Amazon warehouse.

One I can't start til my background check and ID pass is ready and 2nd I can start next Monday.

I want the airport one cos it's not cleaning (fed up of cleaning jobs). Mom suggested I work the 2nd job until the 1st one is ready then quit the 2nd one. Not sure about that tho even tho it would mean I'd get some money coming in as I've literally got £2 left. Both pay weekly and it'll take a few weeks for 1st job to be ready.

They might see it as a dick move though.

Edit: they're both agencies, I'm not working directly with the companies. The agencies already done background checks for Amazon so this why I'm asking.

Should I tell the 2nd agency or tell them after 1st job is ready?