Q.Why are leaves on Red Twig Dogwood bush turning brown
I can’t upload a pictures cuz I can’t figure out how to unlock access. Soooo I’ll try to explain. These leaves looked healthy and green 1 week ago when we planted it. Now the leaves are turning brown, not from edges or tips, but the inside of the leaves are all turning brown. Any idea why?

A new planting needs daily water for the first 2 weeks, then you can cut back a bit.
Adding 2 to 3 inches of hardwood mulch can help with moisture retention.
I would increase water and in a few weeks do a test on the branches. Branches that snap are likely dead, bending they remain alive.
Here is a link with more information.
https://www.gardeningknowhow.com/ornamental/trees/dogwood/red-twig-dogwood-care.htm