If you're just trying to upload it so that other people can download it, then you literally just activate the New button in the Google Drive window (I'm presuming web interface here) and you'll be given a context menu that includes File Upload. You'd select that and go through the usual steps with Windows to navigate to and select the file you wish to upload.
If you're talking about actually creating a Google Doc, then you'd follow the above up to the New button, but go to Google Docs in the context menu and select the Blank Document option from its submenu. Then copy all of your original Word document, paste it in to the Google Doc, then save it.
I have scads of actual MS-Word documents on Google Drive, but don't use Google Docs itself to create and edit documents.
Brian - Windows 10 Pro, 64-Bit, Version 1909, Build 18363
The purpose of education is not to validate ignorance but to overcome it.