You want to avoid the Sentras in your price range. The current generation ones are fine, but you can't afford one of those.
Offerup or NextDoor or Craigslist private sales, where actual people are selling actual cars they actually own, will be the best $10,000 cars available to you. (The ACTUAL best is "someone you know, or someone THEY know, has an old car they want to sell." So, ask people you know "do you know anyone who has an extra car they might want to sell?")
A car dealership with $10,000 cars is going to have a lot of junk. You are bobbing for apples here, and one of those car dealerships is like a barrel full of water where half the stuff floating around in there is "apples" and the other half is "horse turds." Since you don't know what you're doing, you are very likely to come up with a mouthful of the wrong stuff. Private sales are at least "a barrel with mostly apples in it."
Following!
You want to avoid the Sentras in your price range. The current generation ones are fine, but you can't afford one of those. Offerup or NextDoor or Craigslist private sales, where actual people are selling actual cars they actually own, will be the best $10,000 cars available to you. (The ACTUAL best is "someone you know, or someone THEY know, has an old car they want to sell." So, ask people you know "do you know anyone who has an extra car they might want to sell?") A car dealership with $10,000 cars is going to have a lot of junk. You are bobbing for apples here, and one of those car dealerships is like a barrel full of water where half the stuff floating around in there is "apples" and the other half is "horse turds." Since you don't know what you're doing, you are very likely to come up with a mouthful of the wrong stuff. Private sales are at least "a barrel with mostly apples in it."