That particular frame is made by Larry Vs. Harry, called the Bullitt bike, or eBullitt for the electric version. If in the US you may need to do a bit of digging on and offline to find a distributor.
They’re called “bakfiet” or “longjohn” cargo bikes. Similar bikes are made by Urban Arrow, R&M, Bakfiet.nl, and others that aren’t top of mind for me at the moment