In order to save all your photos and videos to your Google Account from your Windows or Mac computer and any time you connect a phone, camera, or storage card, follow the process below:
Back up your cameras, phones, & storage cards to Google drive:
When you choose to upload photos from your phone, camera, or storage cards in the set up, every time you connect your device to your computer, the photos and videos on them will be uploaded automatically (after prompting you the first time) to your Google drive account. Auto Backup uses your Google Drive storage and uploads at full size by default. You can change these settings any time in your Auto Backup Preferences.