Resources
Remember. Track and cite your sources! See How to Cite Other’s Work.
Poly Haven: Great website for textures, models, and HDRIs. Items here are CC0, so you can use them in your project without having to get licenses. Also, there are Blender downloads! You can download a material and append it to your project without having to attach all the images (diffuse, normal, specular) to your texture.
Tileable.co: There are a lot of obtrusive ads with big buttons you have to avoid clicking on, or you’ll get malware on your computer. Aside from that, there is a great selection of tileable textures. The low-res ones can be downloaded for free.
Blendswap: Not a free website, but you can post and download models here. This can save a ton of time if you decide to do a lot of Blender in the future.
cgtrader: More models in different formats. Some are free, some can be purchased. Some are…weird.
Free3D: Free 3D Blender models. And some other formats.