Fellow's ClickUp integration is at the User level - meaning that every member of your team will need to connect their ClickUp account if they would like.
Note: this is a Pro plan (and above) feature
Steps
To set-up, go to User Settings --> Apps & Integrations. You'll find the ClickUp integration card located in the Automation row
Click on the three dots in the upper right hand corner and click Connect.
Select the ClickUp workspace that you would like to connect to Fellow. Click Connect Workspace.
Once connected, you'll see a notification at the bottom of your screen
Once ClickUp has been connected, you'll be able to sync individual action items to ClickUp or link an entire Note Series.