[Including the steps for offloading WordPress Media without using plugins.]
- Bucket Creation
Goto Cloud Storage → Browser → Create Bucket[Text Wrapping Break]Name should be unique id.

- File Uploading
Click on newly created bucket → Upload file → select image

- Copy URL
Click on image → copy the Authenticated URL from the Object Details.

- Goto wp-admin Dashboard → goto image which you need to change→ click on image → replace → edit URL →Paste the URL which copied from GCS→ submit↩

- Update the page/post.
Output
Before

After
