Do u mean just not want to see the warning popups?
Popups could be disabled following three ways -

  1. Configuring Avast automatic operation:
    Click “Real-time Shields - file system shield - expert settings - action”
    Set the showing three options page one by one as your wish. Recommending “Move to Chest” & “No Action” only.

  2. Configuring Avast running in silent mode
    Click “Settings - Silent/Gaming Mode” then switch to Silent mode

  3. Click “Settings - Popups” and then modify the showing time to 0. Obviously this is not recommended.

If any files missed You can review the shield log or the virus chest later.