I have a van with a doggie door cut out the side I want to have Arduino control the door on a linear actuator I'm thinking about RDIF tag for the dog collars so when I leave the van the door go down and steps to go up but when you go into the van how can I make that happen or any other ideas would be appreciated
Sorry, but I don't quite understand the question. I think you are saying you want an Arduino to control a linear actuator to open and close a doggie door on your van. You want the Arduino to base its actions on an RFID in or on the collars of the dogs.
What linear actuator are you using?
Typical Arduino RFID units can only read within a few centimeters. Unless you can train the dogs to get the RFID chips very close to the reader you will have problems. You may have to research longer-distance RFID units. maybe this $85 unit would be enough: https://www.amazon.com/dp/B00UX03TLO/ref=asc_df_B00UX03TLO5496649/