Open-Use Software / Brushes / Rigs / etc.

https://www.blender.org/ (for 3-D modeling and animation)

https://www.electropuppet.com/free-adobe-puppet-templates/  (free Adobe CC animation rigs)

https://www.photopea.com/ (alternative to photoshop)

https://firealpaca.com/download/ (free digital painting software)

https://medibangpaint.com/en/ (free digital painting software)

https://krita.org/en/download/krita-desktop/ (free digital painting software)

https://inkscape.org/ (alternative to adobe illustrator)

https://procreate.brushes.work/category/free-brushes/ (Procreate)

https://beebom.com/best-free-procreate-brushes/ (Procreate) 

https://librium.digital/ (Procreate)

https://www.brushgalaxy.com/brushes/free/ (Procreate)

https://jaejohns.com/free-procreate-brushes/ (Procreate)

https://www.brusheezy.com/free/paint (Photoshop)  

https://www.behance.net/search/projects?search=free+photoshop+brushes&locale=en_US (Photoshop)

https://myphotoshopbrushes.com/brushes/ (Photoshop)

https://www.creativebloq.com/photoshop/free-photoshop-brushes-11121140 (Photoshop)

https://firealpaca.com/material/ (Firealpaca)

https://medibangpaint.com/en/material_kind/brush/ (Medibang paint)

https://conceptartempire.com/free-krita-brushes/ (Krita)

https://krita-artists.org/c/resources/brushes-and-bundles/32 (Krita)

https://imagy.app/free-brush-packs-for-krita/ (Krita)

https://homesthetics.net/free-krita-brushes/ (Krita)

https://conceptartempire.com/clip-studio-paint-brushes/ (Clip Studio Paint)

https://www.clipstudio.net/en/functions/materials/ (Clip Studio Paint)

https://www.brusheezy.com/free/clip-studio-paint (Clip Studio Paint)

https://www.youtube.com/watch?v=nyoDgh62Q-Q (Procreate)

https://www.youtube.com/watch?v=2juwkAgJ6KQ (Photoshop)

https://www.youtube.com/watch?v=DKvZoQ2jViY (Firealpaca)

https://www.youtube.com/watch?v=L48nIiuj4_8 (Medibang)

https://www.youtube.com/watch?v=ubQKVqjfKwE (4 ways to get new Medibang brushes)

https://www.youtube.com/watch?v=xJsfL0ZgTmE (Krita)

https://www.youtube.com/watch?v=ewNQky3RjsA (How to make your own Procreate brushes)

https://www.youtube.com/watch?v=xw4I-SD_oPc (How to make your own Photoshop brushes)

https://www.youtube.com/watch?v=hLB2TUlL-mI (How to make your own Firealpaca brushes)

https://www.1001fonts.com/

https://www.1001freefonts.com/

https://www.dafont.com/

https://www.fontspace.com/popular/fonts

https://www.creativefabrica.com/freebies/free-fonts/ 

https://www.urbanfonts.com/free-fonts.htm 

https://www.fontsquirrel.com/ 

https://fontbundles.net/free-fonts 

https://befonts.com/ 

https://www.youtube.com/watch?v=Eb6m7i0S8yg (Procreate)

https://www.youtube.com/watch?v=IDGh36oanZA (Photoshop)

https://www.youtube.com/watch?v=oYraNgxBReA (Krita)

https://assets.clip-studio.com/en-us (clip studio paint assets, including brushes, gradients, etc)