I have something drawing power from alternator and battery on 1991 Dodge Ram Van B250

I have something drawing power from alternator and battery. Starter is brand new, alternator is brand new, battery is brand new

2 answers
Check for the obvious like an interior lamp being on. Does your key in lamp go off withing 15 seconds? Is your glove box lite staying on? Under hood lamp?
Get your electrical system checked by a Dodge specialist or an auto electric shop. Finding a fault in an electrical system can be difficult for a weekend warrior without the tools, training and experience that you could find in a Dodge specialist.
If you want to find a specialist, here's a directory link for you:
https://repairpal.com/directory?address=48377&car_brand_names=Dodge