Q: How can I get my music up to a level that is acceptable for radio?
This is a situation where I have to wonder whether you are asking the right question.
Perhaps the question should be, "How can I get my music played on radio?"
The answer to that is to write a great song and make a great recording of it. If you can make a recording that will thrill people when they hear it, then the odd decibel or two simply won't matter.
But I suspect that the question is really about how can you get your recordings to sound as loud as commercially released recordings.
Here's a test...
Get hold of a compilation CD of recent chart songs. (If you're serious about getting your music on the radio, you'll have a collection of them already.)
(The reason I say 'CD' rather than 'download' is that CD recordings are not subject to the MP3 or AAC encoding process, either of which will degrade the sound quality and makes comparisons more difficult.)
Now, using the cleverness of your computer, make a new CD with one of your recordings inserted among the professionally-made recordings.
What you will almost certainly find is that your song will be significantly lower in level than the commercially-released tracks, even if you have normalized your recording right up to peak level.
The reason for this is that commercial recordings are always 'mastered' after mixing. One of the functions of mastering is to increase the loudness of the recording. This is done using a combination of compression, limiting and multi-band compression.
There is a lot of skill in this. All of these processes can easily make the mix sound worse, even if it is louder. The trick is to get the mix to sound louder, without significant degradation.
So if you are determined that you want to be able to compete in terms of loudness, you need to equip yourself with the appropriate tools.
Mastering plug-ins are available that will help you increase the loudness of your recordings. They don't work by magic - you have to learn how to use them effectively.
Over time however, you should be able to make recordings that sound as loud as commercially released recordings.
Now all you have to do is write a great song!