I've never understood the common media trope of a teen on their bed reading a magazine on their stomach prompted up by their elbows. Never in my life has that been a comfortable position.
That literally how I read every day. Pillow under my chest helps too.
My kid usually sits perched on the floor and holds the book open with his foot. It looks so uncomfortable but he seems fine with it.
I took all manner of outlandish reading positions when I was young; including that one. Now my body can only handle "lying flat, book on the chest".