Sorry, but that's not really enough information to go by. Could you please provide more information about date of the letter, who sent it, which branch of service and unit Edward Fletcher was in, and the nature of the correspondence? Also, please keep in mind that personal correspondence to relatives of service members would not be retained by the federal government, and even most official correspondence was not permanently retained.
Dear Marquita Fletcher,
Thank you for posting your request on History Hub!
If you have the letter (or a copy of it) and want more information about its contents, could you share some additional details? For example, if you are able to share information about when Edward Fletcher served in the Armed Forces or which branch of the military or unit he served with, then we may be able to direct you to some potentially relevant records like operations reports, unit histories, or other similar records.
In general, copies of personal correspondence from individual service members are not retained as permanent federal records, so if you do not already have a copy of the letter, it is not likely to be found at the National Archives.
If you are looking for information about Edward Fletcher’s military service, we suggest that you request a copy of his Official Military Personnel File (OMPF). OMPFs for those who served in the U.S. Armed Forces and who were separated from the service before October 2002 are in the custody of NARA's National Personnel Records Center (NPRC) in St. Louis. In many cases where Army and Air Force personnel records were destroyed in the 1973 fire, proof of service can be provided from other records such as morning reports, payrolls, and military orders, and a certificate of military service will be issued. Navy and Marine Corps OMPFs were not affected by the fire. Please complete a GSA Standard Form 180 and mail it to NARA's National Personnel Records Center, (Military Personnel Records), 1 Archives Drive, St. Louis, MO 63138-1002. Veterans and their next of kin also may use eVetRecs to request records. See eVetRecs Help for instructions. If there is any information requested by the form that you do not know, you may omit it or provide estimates (such as for dates), but the more information you provide, the easier it will be to locate the correct file if it survived the fire. For more information see Official Military Personnel Files (OMPF), Archival Records Requests.
Please note that Official Military Personnel Files (OMPFs) for those who served in the U.S. Armed Forces and were separated after September 30, 2002 (Army); after September 30, 2004 (Air Force); after 1994 (Navy); and after 1998 (Marine Corps) are available in electronic format via https://milconnect.dmdc.osd.mil/milconnect/.
We hope this is helpful. Best of luck with your research!