The prompts macOS shows you

Notifications. The first time the app opens, macOS asks whether Threadbear may send notifications. Either answer is fine: with them on, the app tells you when a thread needs you and you aren't looking at it, which helps most when your threads run on Full access and you've wandered off. You can change it later in System Settings > Notifications.
Folder access. When an agent reaches into a protected folder, such as Desktop, Documents, Downloads or Dropbox, macOS asks whether to allow it. Click Allow if you want agents working there, or Don't Allow if not. You can change your mind later in System Settings > Privacy & Security > Files and Folders. Starting threads in ~/ThreadbearThreads keeps these prompts away until you choose a folder that needs them.