An interchangeable lens camera or DSLR will almost certainly generate a need for another lens, and therefore kill your $500 budget. I would suggest you look at Panasonic. If size is not critical, the FZ80 is a nice camera for $400. If you want something smaller the ZS travel series might be interesting at $500. I have found the ZS50 to be handy to carry around, but the viewfinder is small and gripping a small camera not always secure. These are both small sensor cameras, but millions of users are very happy and don't see a problem with the results. Crop in camera and you should be fine. Panasonic is also offering a 3-year warranty on many models, no small advantage.

I would apppreciate your help. I am looking for a good basic camera with a viewfinder.
Up until a year ago, my Sony Cyber-shot with no viewfinder took good basic photos for me. My interest was photos of my grandchildren.

But this past year I have spent a lot of time traveling in an RV. Most of my shots during that time were done outdoors, And needless to say, most shots were a disaster.
I would like a good basic camera with viewfinder for around $500. I am in my late 70’s and no expert.
I have seen the Canon Rebel T6 advertised at Costco for @ $500.
I have also seen mentioned the Canon T6i at B&H. I am not sure what the difference is. Maybe I should be looking at something else entirely.
But any suggestions or direction would be appreciated. Thank you.

Wow!!! I knew this was the place to ask for help, but your responses have been incredible. Thank you all for taking the time to advise me.
I am checking out all the various suggestions, and some, including the bridge camera, I had never heard of before. Your comments and suggestions are forcing me to re-define more exactly what am I looking for in a camera.

... As the sole driver of our Class B RV, I want a simple automatic camera that I can hand to my husband to catch a scene while I am driving.
... I don’t need to be changing lenses anymore. There is no room in this van to store them, let alone spread things out on a mini table to change them. I need one good lens.
... I am not into macro at this time. A good single zoom will be adequate.
... I enjoy taking short videos of my grandchildren, but I think any camera would be adequate for my purposes.
... I now realize that physical camera size really does matter. I want a camera that I will tend to pick up and take with me. It won’t be the size of an iPhone, but I hope I can find something good enough that won’t be too, too big.
I am not an expert, far from it. You have given me some wonderful, varied suggestions.
Thank you.

Wow!!! I knew this was the place to ask for help, but your responses have been incredible. Thank you all for taking the time to advise me.
I am checking out all the various suggestions, and some, including the bridge camera, I had never heard of before. Your comments and suggestions are forcing me to re-define more exactly what am I looking for in a camera.

... As the sole driver of our Class B RV, I want a simple automatic camera that I can hand to my husband to catch a scene while I am driving.
... I don’t need to be changing lenses anymore. There is no room in this van to store them, let alone spread things out on a mini table to change them. I need one good lens.
... I am not into macro at this time. A good single zoom will be adequate.
... I enjoy taking short videos of my grandchildren, but I think any camera would be adequate for my purposes.
... I now realize that physical camera size really does matter. I want a camera that I will tend to pick up and take with me. It won’t be the size of an iPhone, but I hope I can find something good enough that won’t be too, too big.
I am not an expert, far from it. You have given me some wonderful, varied suggestions.
Thank you.