Hi, need your help!

Second ride of my training wheels and getting an odd loud squeak from my rear wheel.

Even happens when my bike is suspended in the air. Quiet one moment cured! Then sounds like a balloon deflating.

Any suggestions what to check?

Superstar told me to squirt a bit of oil in case it’s an O ring but wondering if it’s the free hub or hub bearings.

Checked and replaced my tyre as it sounds like rubber on on metal.

If you ride hard enough, you ignore it lol