I wanted to know if the music I created with feel good is commercial, and in the creation in magix music maker if it can be released commercially free of charge, because it seems that it was royalty free
No. Nothing that comes with the program has a commercial license. You would need a commercial license and you can purchase it on Producer Planet. All Magix Soundpools and Songs are royalty free, but the intended use can be different, and for that, you need the appropriate license.
Royalty free means that you don't have to pay royalties for using the material, but you do need to pay for the license to use the material.
See this Import Post and read the manual about licensing.