Voodoo Practitioners know as Bondye to be "The Vodou God." Or some would say "The creator." Bondye is the one and only God of this religion. The Loa however are eaisly mistaken to be Gods , but they are infact Spirits. Bondye uses these spirits "The Loa" as his way of spreading his own will.
Just about if not all work with one particular Loa, but give equal respect to them all. I work with Mambo La Sirene, also referred to as the Lwa of wealth. It is good to always lay out offerings to the Lwa you work with or serve. I've also worked with Papa Legba. Papa Legba is one of the most interesting of the Lwa. If you've ever made a statement saying "I've just finished speaking to Papa Loko" (as an example) Though if Papa Legba hasn't granted you permission to speak with the Lwa your statement is false. Legba stands between, the Physical world (mortal world ) and the spiritual world (( The Realm of the Lwa.)) Therefore to speak with any of the Lwa you must have Permission from Papa Legba.
If you work with any Lwa specfically please post them below and whatever you want to add on, I look forward to reading. Thank you. :D