Yes, according to the AWS documentation, you can see your AWS storage costs for free tier usage in the billing console. In there you should see (when logged in as an admin) the Top Free Tier Services by Usage table. They mention the table does not appear if any of these conditions are met:
You use an AWS service that doesn't offer a free tier.
Your free tier has expired.
You access AWS through Amazon Internet Services Pvt. Ltd (AISPL).
You access AWS through AWS Organizations, but you don't use the master account.
If you see your usage, use the basics of AWS billing to get an estimate of what your costs would be using AWS paid services. AWS billing is not straightforward, its kind of like reading tea leaves. If you're not familiar with how Amazon bills, you can check their documentation, or I found a good billing basics article in NetApp's blog.