Which side of the bay? (there's no bridge...)
If south Dive Wederfoort is nearby - don't know them at all. If north
Trunk Divers is I believe the next closest shop farther west at Kokomo Beach. Trunk Divers will have rentals If you plan to shore dive - buy their guide - most shops sell it.
Your villa is likely south as most of St Michel is also,
Bring any dive gear you buy b4 then - it will be better than rentals. Divi will manage to get your bags over within a day if they can't fit on the plane - they're small planes but then so is the passenger list.
Trunk Divers guides which you may want to consider for your first dives. It's actually a good dive also - nice reef out front, we found seahorses at about 40' and there's a non-penetrable wreck at about 80; to the south - you can view if from much shallower also - the water is super clear. Sometimes called Trunk Bay or Varsenbaai. Hug the beach as you swim back - in 6-8' of water turtles feed there about 100 yds. to the south of the beach. They also guide at other sites.
Many beaches on Curacao are also easy entry beach dives. Most have a dive shop onsite for tank/weight rental also, None do on Bonaire so bring the minimum needed as you'll be leaving the truck open.
For boat dives - back down Weg Bullenbai to Piscadera Bay - on the south side is the Hilton - Caribbean Sea Sports is based there. There may be a closer boat but theirs is nice - and diver safe as it's a jetdirve - no prop.
Boka St Michel is a pretty quiet area. Centrum Market is just a couple lights south of the airport rotary - we stop there before driving out but we stay farther west. The farther east/west you get from Willemstad the quieter everything gets. And there's a lack of restaurants but Willemstad is reasonalby close - there's maybe 1/2 dozen options in Piscadera Bay also - sort of a resort/convention area.
Curacao shore diving is about as easy as it gets - most shops are on the beach - most beaches are sandy to deeper water and then thre reef starts. In almost every case it parallels the beach also - no reason to go deeper as it flattens out and gets sandy in many places past about 100'.
Bonaire entries are a lot rougher - there's both sharp ironshore on-shore and also in shallow water - often you climb over it. Spiny urchins love it also so a MUST for Bonaire is good treaded boots - unless you only dive the resorts or few sandy entries.Or boat dive - should dive some of the Klein Bonaire sites from a boat anyway.fyi the Advanced sites on Bonaite tend to be south around the lighthouse or north in Slagbaai Park. IMO not worth the trouble for 4 days.
This site is somewhat dated but it gives you a good idea of what to expect - there's entry photos.
Scuba Shore Diving Region: ABC Islands