Auto Tagging of Customers based on CSV list

Had a question regarding auto-tagging of customers. Is there a way/app to automatically tag customers when they make accounts based on a CSV (or any other format)?

So if we have a CSV of about 1000 emails, and if a customer with “xyz@email.com” creates an account, is there a way to check if the email exists in the CSV list and then tag them appropriately?

Additionally, if we upload a new list, it’ll also check if any current users exist in that list and then tag them as well.