Hi John and welcome to the forum.
Your correct, this is a photography problem.
I believe the darker pictures when on auto, is because your EV is set to -3. That’s three stops underexposed. These little sensored cameras really pump the brightness, so it’s good to be a little under but that would be a third of a stop (.3) or if your shooting raw you can be up to a stop under (-.5 to -1.0).
On your manual settings the EV set to +.7 will tend to over expose by 2/3 of a stop. Everything is blown out so there is no color. Do you use your histogram?
Search basic photography on YouTube and find someone you can stand listening to that can help you understand the basics a bit better. This guys pretty good, there’s a ton of this sleet of stuff.