https://wccftech.com/latest-gmail-for-ios-update-will-let-users-add-attachments-from-files-app/

Great news, Gmail for iOS users. A new update for iPhone and iPad will let you add attachments to your email straight from the Files app.

The Gmail for iOS app has been around for a long time and if you are a man of culture then you probably use it to handle email on a daily basis. Admit it, the first-party Mail app is simply trash and there's a lot more which the official Gmail app offers.