Strongly recommend “The Sands of Iwo Jima”, starring John Wayne. The raising of the flag will give you permanent goose bumps.
Try “Flags of Our Fathers” by Bradley and “With the Old Breed” by Eugene Sledge. John Wayne got killed before Iwo Jima battle was a week old. Ira Hayes was one of the men raising the second flag in the photo.
I just lost my grandfather a few years back. He was there. Though he never really spoke about it much. My cousin spoke at his funeral. Most of us had never heard the story till then. They both shared something in common beyond lineage, they both wore the same uniform. The United States Marine Corp.
Still proud of you Grandpa. You made us all proud. God Bless you and all who served.