You can submit an assignment in Google Classroom under the "Classwork" section on the desktop site or mobile app.

How to upload a photo to Google Drive If you took your photo on a device that doesn't have access to Google Classroom, upload it to Google Drive.

To log in to Google Classroom, begin by opening a web browser and navigate to classroom.google.com Next, enter a personal, organisation, or educational email account and proceed by pressing Next.