I would like to make audio quality similar to this https://youtu.be/LZgeIReY04c (at 0:12) in Audacity.
Try playing with the “Distortion” effect: https://manual.audacityteam.org/man/distortion.html
The “Hard Clipping” setting will probably be close, but you may like to try other settings.
Also, reducing the sample rate (“Tracks menu > Resample”) will make the sound more muffled. Try resampling down to 8000 Hz (the smaller the number, the more muffled it will be).
“Helmet radio” plugin gives good clipping, without the result being deafeningly loud
https://forum.audacityteam.org/t/how-to-make-your-voice-like-this-presumably-helmet-radio/47292/21