Photofiltre is a free Photo editing program that I have used for years. I really like it's clean interface if you are trying to get something simple done.
I won't say it is as good as Adobe Photoshop Elements 15 because Adobe really has a vast amount of filters and so on.

I chose to do some of my tutorials in video and I started with this program. One reason I did this was because there were so many non English tutorials out there (because this program has other versions) and I couldn't find simple ones in English.