This license is only applicable to the music from this page, you must refer to the general license for all other music tracks from Royalty-free-music.pro
You can use the music tracks from this page for personal or non-profit projects: Videos (Youtube, Vimeo,...), Film, background music, Website,...
The music is under the creative commons licensed "BY-NC-ND 3.0", you have to credit the author when you use the music (for exemple: "Music from http://www.royalty-free-music.pro").
You can find the license details here:
You can edit the music by cutting it or mixing it with a voice but you can't use it to produce your music (remix, song, etc.)