That's very impressive! They look like they could have been burned with stamps like these.
No problem!!!
Capital letters: Walnut Hollow Hotstamps Uppercase Alphabet Branding and Personalization Set for Wood and other Surfaces https://www.amazon.com/dp/B0019N4VSO/ref=cm_sw_r_cp_apip_qZ3nYNo4V4dhs
Lower case letters: Walnut Hollow Mini Hot Stamps Lowercase Alphabet Branding & Personalization Set for Wood, Leather & Other Surfaces https://www.amazon.com/dp/B01KTBQU3A/ref=cm_sw_r_cp_apip_kDRK8wBD2b4RL
Wood burner: Walnut Hollow Creative Versa Tool with Versa-Temp Variable Temperature Control and 11 Woodburning Points https://www.amazon.com/dp/B005P1TRAS/ref=cm_sw_r_cp_apip_l5txnwxGFubDB