Create minecraft texture pack?

I have a question about Minecraft texture packs? Do you know where you can create texture packages without downloading a program?

You only have to edit the textures, usually .png files, from an existing texture pack, with a program, e.g. Paint, or you can create your own, also e.g. With Paint, create your own files, but pay attention to the folder structure you should find it in the Minecraft gamepedia wiki.

Good other free programs to edit / create the images

Thank you