NG are under the command and control of Maj. Gen. William Walker.

“Right now, we have approximately 7,000 National Guard soldiers and airmen on the ground in support of the lead federal agency, and we are building to 21,000 for the upcoming inauguration,” Army Gen. Daniel Hokanson, chief of the National Guard Bureau said during an inauguration security briefing with Vice President Mike Pence today, according to a media release.

“They are under the command and control of Maj. Gen. William Walker, the Commanding General of the D.C. National Guard, and are providing security, communications, logistics and coordination with all supported agencies.

https://www.militarytimes.com/news/your-military/2021/01/14/national-guard-dc-presence-will-swell-to-26000-for-biden-inauguration/

Chief of the National Guard Bureau

In May 2020, Hokanson was nominated for appointment to the rank of general and assignment as the chief of the National Guard Bureau.[11] He was confirmed by the Senate on July 20, 2020[11] and assumed office on August 3, 2020.[12]

https://en.wikipedia.org/wiki/Daniel_R._Hokanson