Use the FM/AM switch on the back to toggle between FM broadcast and all other modes (AM, LW, SW, SSB).
He didn’t touch the radio for a week.
The ATS-20 (and the upgraded ATS-20+) are compact SI4732-based all-band radio receivers popular in the ham radio community. Because these are often sold as DIY kits or unbranded imports, a single "official" printed manual can be hard to find, but you can use the following guide for operation and resources. ats-20 radio manual