No. The USPS does not offer tracking on first class letters or cards.

You can get tracking information on all USPS service levels EXCEPT USPS Flats and Letters. USPS doesn’t support tracking for Flats and Letters.

If you absolutely need tracking, you’ll need to use Parcel as the predefined package for your USPS Flats and Letters shipment or enter an actual package size and then not select First Class for shipping.

First Class Package (as compared to First Class) does offer tracking.