To buy a car in Engpsh, you can use the phrase "to purchase a vehicle." You can also say "to buy a car." Here are a few more phrases that might be helpful:

"I'm in the market for a new car." (This means that you are looking to buy a car.)

"I'm interested in financing options for a car." (This means that you want to know about different ways to pay for a car, such as taking out a loan.)

"I'm looking at different models and makes." (This means that you are considering different types of cars from different manufacturers.)

"I'm negotiating the price with the dealership." (This means that you are trying to agree on a price with the place where you are buying the car.)

I hope this helps! Let me know if you have any other questions.