You can send a short test to ACX before you read a whole book.
https://forum.audacityteam.org/t/how-to-send-a-test-to-acx/49588/1
That and the sample has to conform to their technical standards: Peak, RMS, Noise.
When you apply Limiter, remember to change the limit setting to -3.5 rather than the default -3.0. If you leave it 3.0, you have no room for error. Any mistake and the work will fail standards.
Koz