Photopea is a free image editor that seems almost too familiar to Photoshop - in looks, and in getting the job done. If you're familiar with image editors, then this should be a walk in the park for you. If not, it might take a second, but the possibilities are endless (plus, no download required!).
Now, given that this is a whole beast of its own, I will not give a tutorial on how to use it (you can find that on YouTube in your own time); but I'm going to briefly edit a picture, and show you a few different things you can do.
Photopea lets you import content from native editors (.PSD, .XD, .sketch, .PDF...) or start with a brand new project of your own.