I created an account on Pinterest Using Tor Browser. Then I uploaded an image from my phone on Pinterest(Tor Browser), would anyone know it was me who uploaded the image?
Possibly. Does the image have identifying metadata? For example, images will often store the type of camera, GPS location, date/time, and more as metadata. Pinterest themselves may strip some of this metadata off before sending the files to other users' devices (I'm not sure if they do or not), but Pinterest themselves would be able to view this metadata.
The Tor Browser will not leak information, but any information you supply (such as email addresses when making the account, metadata in images that you upload, etc) may be used to identify you if you are not careful.