You can purchase a car from an individual, or you can go to a dealership. However, it's a good idea to learn about the realities of the decisions you make. It's often your best bet to realize the risks you would take buying from an individual and the benefits that also come with heading to the dealership. Here is more on this.
Individuals have no responsibility to be honest
When it comes to protection for those who purchase vehicles from an individual, most states have very little in the way of protection or recourse for them should they buy a car only to find out that there are mechanical issues with it. In fact, in many cases simply adding "purchased as-is" on the bill of sale is enough to protect the seller.
You may wonder why a buyer would go along with this and the answer is that it's so common for sellers to add this to the bill of sale that buyers would have a very hard time even buying a car from an individual at all if they didn't agree to sign such a bill of sale. A lot of times individuals will know there is something wrong with a car and they will do their best to patch it up so it will last a while before the buyer knows there is an issue and when the problem is found, it is the buyer that gets stuck handling the bill.
Dealerships have a reputation to protect and a responsibility to sell sound vehicles
When you go to a dealership, you know that their mechanics have gone over the car before putting it on the lot for sale and they would have addressed any mechanical issues that were found. Also, a dealership can't get away with repeatedly selling lemons or their reputation would be tarnished and it would cost them a lot more in future business than it would have cost them to fix mechanical issues in the first place.
Another thing that you will be glad to know is that in most cases, the cars purchased at a dealership as used cars will come with warranties. While these warranties won't last nearly as long as if you bought a brand-new car, they generally last long enough for you to know that you purchased a sound car and have any little issues that may have been overlooked fixed.
Visit a dealership like a Nissan dealership to see what cars are available.