You can use an app like Tailwind to schedule your uploads and add them automatically over a period of time but you still have to do the Titles and descriptions manually.
I think you can get your account suspended if you add more then 50 images per day so It will take some time.
Definitely don't try to upload them all at one time. Upload a few each day. This will make your page look more active also. If you are only uploading a few a day, you don't need automation tools to do that.
Follow Pinterest rules and abide by them. As well as you can post some image or content manually not use any app. Obviously don't post all images a day. Post them manually.