Or you can go the destructive removal route. It is a Shimano BMX freewheel and not valuable.

If you are not familiar with this route, you need a hammer, a punch, and a pipe wrench.

1. With a tire mounted on the rim and inflated to a low pressure, place the wheel on the floor or work bench with the freewheel facing you.
2. Align the two round divots in the retaining ring/outer bearing race at 3:00 and 9:00 o'clock.
3. Place the punch in the 3:00 o'clock divot and hammer it towards the floor to loosen threads.
4. Remove the retaining ring/outer bearing race while the wheel is in a horizontal position.
5. Once removed, revealing many ball bearings, place a bowl/container over the freewheel, and rapidly flip the wheel 180 degrees.
6. Use a pipe wrench to remove the inner body from the hub.