1) Install Better Uploader (free plugin):
https://bubble.io/plugin/better-uploader-1648049058728x6296215566200340002) Select some files inside of a Better Uploader
3) Run the Compress Image(s) action. You'll need to provide a maxium size (in MB) and a maximum width (resolution). The lower the width, the lower the resolution. It is recommended to use one of the following: 3840(2160p), 1920 (1080p), 1280(720p), 720(480p).
4) Once the file(s) have been compressed, the Image Compression Process is Complete is fired. Run the subsequent workflow actions there (notably Better Uploader's send file(s) to cloud action
EDITOR:
https://bubble.io/page?type=page&name=better_uploader_companion&id=plugin-testing-page&tab=tabs-1