You should be able to browse their local timeline (from the point of view of qoto) like this:
https://qoto.org/web/timelines/public/remote/gab.com
This is probably not everything however, due to the way activity pub works. Some clients let you request the timeline straight from the instance itself, if you really don't want to miss anything. So far I only know of Subway Tooter and Fedilab that have that feature, both Android clients.