BeatBuddy
https://www.singularsound.com/products/beatbuddy?gclid=CjwKCAiAq4KuBhA6EiwArMAw1Ca694OJKJwMsFjSfzOUDpQY3Z-QhWYPiheYDeCOVnLQEAFHp4kpHxoCuMoQAvD_BwE
Very easy to use and modify for your own needs. There are many full songs available on their forum site for free, as well as many "styles".