Today my Google Drive was upgraded to the new Google Drive. It has a clean interface but there are a few feature differences. The checkbox feature is now gone. It use to be you could put a check mark next to multiple files in order to select them to delete or move the files.
Hold Down the Control Key
If you are on a PC you will want to hold down the Control key as you select multiple files in Google Drive. If you are on a Mac, hold down the Command key.