Increasing volume without distortion

I recommend the ToneBooster’s “broadcast” plugin (V3 is free)
https://forum.audacityteam.org/t/free-v3-toneboosters-plugins/64538/3
It’s a multi* [3] band compressor, & limiter combo. It looks complicated but it has presets …

[ * Audacity’s native compressor is only single band ].