Image Trace for Coloring interior with illustrator in easy way for advanced output.

At 1st you can search on

• shutterstock 
• istock

for this kind of keywords

• babt animal coloring pages
• baby cat
• baby dog
• baby elipant

save 50 images per animals with different folders.

After finishing this colection, You Should open your illustrator and insert or placed 50 images per animals.

create new file with 50 artboards with 800x800px per artboard.

Then select image and click the trace panel.

Then manage this values:

• Threshold: 200 - 215
• paths: 80% - 83%
• Conrners: 96% / 95%
• Noise: 5px

Then

• Create : Fills
• Check : Snap Curves To Lines
• Un check : Ignore White

Then

"Expand" and "un groupe'' all images.

Then Delete the background whiten fills, don't delete the animals whiten fills.

After that, you should Resize all images for 50 artboard with 800x800px per artboard.

Finally save on Eps10 and ai2020