If you are not using Wazaterm, you can stop billing for the Wazaterm instances by suspending or terminating the instance. The difference between Suspend and Terminate is as follows:
Suspend saves the currently running process to the Swap area and then terminates the instance; Resume restores the processes and you can use it from the suspended state. (This is generally called hibernate.) Since the process is saved to the swap area, the suspend/resume time will be proportional to the swap memory used. Suspend/resume does not change the memory or CPU type, it behaves like sleep on a PC.
You can change the memory or CPU type by terminating it. In this case, the running process will be terminated, which is the behavior of shutdown in PC.
Suspend/Terminate takes some time, so you can't use the terminal as soon as you open the screen like a laptop. This can be a bit frustrating. To avoid this, Wazaterm allows you to use a Webhook for each terminal. There is a curl command in the Webhook section of the top page.
If you simply put this in your crontab, you can suspend/resume the terminal at the time you need. I also work with the iOS focus and shortcuts app to enable location-based resume/suspend of the terminal. Please refer to the following link to set it up.