Keegan here from the Shopify Guru team.
Might be hard to give that information to customers, as it would require an API call to the postal provider for that tracking number, assuming they allow that information to be received. Might be possible with some coding to generate an "Should arrive from X (7 days from ship date on order) to Y (10 days from ship date on order). but that would require hiring a Shopify Expert.
An alternative solution may just be to provide customers the power to check up on the orders with one of the apps below!
Hopefully this helps, thanks for your post!