When I type this code: emulator @reactto run the emulator it shows:

emulator: The term 'emulator' is not recognized as a name of a cmdlet, function, script file, or executable program.

I don't know why this code is not executed in the terminal. Is it because of the path?

Previously, the emulator was working without any problems. Then I formatted my computer and installed the emulator and this problem appeared. I don't know why. Android Studio was deleted more than once and more than one emulator was downloaded, but to no avail.Knowing that, I tried the methods on the internet and had the same problem.I do not have ANDROID_HOME, if necessary, what is the correct path?

I don't know what he means here. I sat for more than a day
Use '@foo' or '-avd foo' to launch a virtual device named 'foo'

I hope you can help me. Thank you in advance!!

Error code:

INFO         | Android emulator version 35.3.11.0 (build_id 12836668) (CL:N/A)
INFO         | Graphics backend: gfxstream
ERROR        | No AVD specified. Use '@foo' or '-avd foo' to launch a virtual device named 'foo'