Enriching initial contact data for my new CRM

Hey everyone! I'm FINALLY implementing a CRM (Copper) for my boutique agency and am trying to clean up the data from my initial contact list.

Problem: I have an initial list of 700 emails but the accompanying contact info (Name, Company, Job Title, Company Size, Industry, etc) isn't well kept and I don't want to manually update all of this information.

I believe I can upload this CSV of email addresses to a tool that will automatically populate all of the above fields based on the tool's database. (I've been calling this data enrichment, please correct me if this is the wrong term)

I am trying to do this in Hunter.io but struggling to figure out how to update the data points after uploading my email addresses.

Questions:
1) What is the best tool to solve this issue? (a solution that is effective and affordable)
2) Where do I need to go within this tool to update the data points for each email address?

Thanks!