The answer to this question depends on the specifics of your situation. If you and your ex are already in the midst of a divorce or child custody battle, then the court may order you both to attend mediation in an effort to resolve your issues. However, if you are not currently involved in any legal proceedings, you cannot force your ex to go to mediation.
Mediation is a process whereby two parties meet with a neutral third party (the mediator) in an attempt to reach a mutually agreeable resolution to their dispute. The mediator does not make decisions or impose solutions; rather, they facilitate communication and help the parties identify common ground. Mediation can be an effective way to resolve disagreements without having to resort to litigation, which can be costly and time-consuming.
If you think that mediation might be helpful in resolving your differences with your ex, you can try reaching out to them directly and see if they are willing to participate. If they are not interested or refuse to mediate, then unfortunately there is nothing more you can do.