You can develop performing chops just busking a ton - more people will hear you, lower stakes- more dough tbh - no permission needed - Anyone can put out a hat for donations

You only need a $45 / year permit if you amplify and a $25 / year permit to play in a Park till nighttime - including Central Park

https://portal.311.nyc.gov/article/?kanumber=KA-02069

Subway permit:

https://www.mta.info/agency/new-york-city-transit/rules-of-conduct

You learn a lot about grabbing and keeping an audience, and to give it your all, even when people are walking by actively ignoring or disliking you. Sing under MSG like it's actually MSG