Is there a good way to get your sons to stop fighting all of the time, they are 9 and 10yo?

Yes: Parenting is one of the toughest jobs out there! from my perspective being firm, and setting boundaries of acceptable behavior is of paramount importance. Now the difficult part is to enforce the consequence when the boundary is breached; which can be anything from a "time-out" (usually 1 minute/year of age) to restricting a privilege or activity. Remember to tell the child they are loved.

Yes: 1, 2, 3 magic; and learn each boy's love language and help them express themselves to each other with those things in mind. A child's behavior often is an expression of issues the parent has and expresses in some way the child can perceive, often intuitively or subconciously. Awareness of the family dynamic as a whole can be very important.