Uploading files to Google Drive
Full instructions here:
The maximum file size for an upload is 5 TB. However, once you have uploaded more than 750 GB in a day, you cannot upload any further files that day. (So if you upload a 1 TB file, you'll be able to upload the whole thing, but you won't be able to upload any further files that day.)
In the browser
Go to https://drive.google.com/
You can just drag and drop files into your drive to upload them directly.
Or you can click "New" in the top-left and select "File upload" or "Folder upload", then navigate to what you want to upload.
In the app
If you have the Google Drive app on your computer (https://support.google.com/drive/answer/2374987/back-up-amp-sync-files-with-google-drive-computer) then there will be a Google Drive folder on your computer.
Any files you move into this folder will be automatically uploaded to Google Drive, and vice versa.