Here are some links to the websites of the software that I most often use:
Blender: blender.org (3D software, which can also be used for video editing, 2D animation and literally anything else)
Inkscape: inkscape.org (For making vector graphics)
Gimp: gimp.org (Like Photoshop, but free)
Krita: krita.org (Similar to Gimp, but more useful for digital drawing)
LMMS: lmms.io (For making music)