Where to Find and Catch Jangmo-o
From Pokemon Go Wiki
Jangmo-o are found and captured in Nest and Habitat locations.
Nests
Jangmo-o Nests are locations that consistently spawn Jangmo-o.
Habitats
Jangmo-o Habitats are spawn locations where Jangmo-o 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: