Hey Bob,

I think that Christopher Schlegel's lesson on left hand technique would help you greatly with this particular matter.

https://www.guitartricks.com/lesson/10654

However, it would probably serve you well to do the entire 5 lesson tutorial, starting with how to hold a pick. You don't want to pick up any bad habits at this early stage.

I think that you would get more bang for your buck if instead of holding a chord for 30 seconds, you instead just try to "grab" the chord (at a comfortable speed), then plucking the strings one at a time to isolate any fingers that are out of position. Then immediately release and grab again - over and over. You'll acquire muscle memory much quicker that way.

And always be mindful that your fingers are contacting the fretboard at a right angle (perpendicular). You may need to rotate your wrist under the neck a bit more to do this. In your picture, some of your fingers are less than perpendicular.

Sascha