Where to Find and Catch Cherrim
From Pokemon Go Wiki
Cherrim are found and captured in Nest and Habitat locations.
Nests
Cherrim Nests are locations that consistently spawn Cherrim.
Habitats
Cherrim Habitats are spawn locations where Cherrim is likely to be encountered, but not guaranteed the way a Nest is.
Additional Tips and Information
Best Nests
If you know a really good nest or any of the nests above is really good, list them here: