If you have Acrobat Reader on your computer, download the pdf form here https://www.gsa.gov/forms-library/request-pertaining-military-records and you can type in the sections highlighted in blue. You will still have to print and mail the form.
Dear Mr. Potter,
Thank you for posting your request on History Hub!
To type directly into a .pdf form, you will have to first download it to your computer. You may then open the file in Adobe Reader in order to fill in the form with typed text. For more information regarding this subject, please visit Adobe's webpage. https://helpx.adobe.com/au/acrobat/using/filling-pdf-forms.html
We hope this is helpful.