Step 1: Add the Element Scanner in your page. This element will define the are of camera.
Step 2: Add the Action Start Scanner at Workflow area.
Step 3: Add the Action Stop Scanner at Workflow area.
Step 4: Add an element Text to get the result of element Scanner
Demo Editor:
https://bubble.io/page?id=vanmo-sample&tab=Design&name=qrscan&type=page