Lil Nas X is on the ‘Old Town Road’ to recovery … in his first public appearance since wandering the streets naked and allegedly charging at police officers in Los Angeles.

The 26-year-old Grammy winner popped up in L.A., rocking the heck out of a jean jacket and cowboy boots as he ran errands in Santa Monica. He looks healthy and well-rested … even spending some time in a local park before heading off in a white Jeep.

This comes after undergoing inpatient treatment, following his bizarre August 21 arrest.

He was charged with three counts of battery with injury on a police officer and one count of resisting an executive officer after cops allege he went after them during a nude stroll he was taking through the San Fernando Valley.

When police arrested Nas … they thought he was high on drugs, so they took him to a hospital and later transferred him to jail.