Google will send you an email that says, “Your Gmail is almost out of storage” hoping that you purchase more space. You will be shocked how many people upgrade without even trying to clear out old and useless emails with attachments.
Use this link to see how much storage you have left. https://one.google.com/storage
This below is how it will look.
Scroll down until you find this the Elephant. You will need to click the link that says Free Up Account Storage. Once you click, it will give you the option to permanently delete files. It separates large files in Google Drive from attachments in Gmail and even large videos and pictures.
After reclaiming your storage space, you will find that you were wasting half of your storage on things that no longer matter.