The reality television star tells TMZ ... she let her daughter Sophia pick out her first car -- and, out of all the electrics and hybrids she checked out, the Tesla Cybertruck Cyberbeast Foundation proved to be her fav.

FA says she and her daughter are picking up the car next week ... and, then Sophia's gonna customize the chrome car with her own aesthetic -- something she'll have a while to do before she starts driving it on her own ... since she's still only got her learner's permit.

While fans can expect to see more of Sophia's driving journey on social media in upcoming months, Farrah says her daughter's focused on getting her license ... not putting the Cyber-cart before the horse.

It's an expensive gift for her daughter too ... taking a $123K chunk out of Farrah's wallet -- who you may remember drove a used 2009 Dodge Neon when she was on "Teen Mom."

Farrah's already posted several snaps of her daughter in the lead-up to the big purchase ... showing her on day one of driver's ed, and even posting a pic of the 2 of them on a showroom floor looking at some luxury vehicles.