Yep, shingle color is on the lighter side and don't have ridge vents.
Wouldn't it still help a lot to have radiant barriers on top of
shingles if I can't put them under shingles until the shingles need
replacing and can't get into the crawl spaces in the attic?

Thanks and thanks for the Google suggestion!

Hi,
Shingle color, roof vet matters. Do you have good ridge vent?
Google earth engineering for related topics.