Sometimes you need photos to add to a blog post or design or presentation... Navigating the licenses has always been hard. But thanks to "Creative Commons 0" license, it really isn't anymore. This license means: do whatever, commercial or non-commercial purpose, no credit needed (though appreciated).
Below are a few sites I found recently. All their photos are CC0-licensed. You'll rarely find humans in these photos because that's even more complicated, but hopefully there are enough beautiful images for most purposes. And most of these photos are stunning indeed!