Hot damn son. The HW-101 is a great old rig. I learned to operate on my Dad's HW-101.
If you just want to listen, here's what you do. Plug in headphones or a speaker. There is a speaker jack in the rear.
You put the two switches under the meter all the way to the left.
Crank up the RF gain
Turn it on. (Increase the AF gain)
Use the band selector to select a band. Use the band selector to select LSB, USB, or CW. Tune is for tuning the radio to transmit. Don't touch it for this.
Tool around for a signal.
Tweak the signal with the driver preselector knob.
Enjoy some HAM radio.
Real radios glow in the dark.