After clicking to try and paint, I see the missing texture error warning.
Blender Guru's video helps explain it. https://youtu.be/nht2RoYBUfA?t=212
I know 10 images may seem excessive, but I know a lot of new people may get lost and would need it.
- First, create a new image or open an old one. (I will create a new one)
- Create the image. (mine's name will be "Untitled")
- You would get a black image.
- But you still can't paint. That's because the image isn't connected to the texture of the model.
- Go to "Shading" from the top bar.
- Add a new image texture. (Add>Texture>Image Texture)
- Connect the nodes. (Color-Base Color)
- Press the Image button and choose the image you created or opened before. ("Untitled" in my case)
- Now you can paint!