Checkout Order of Execution documentation: https://docs.unity3d.com/6000.0/Documentation/Manual/execution-order.html

You can change order of execution like in this thread with an Attribute: https://stackoverflow.com/questions/27928474/programmatically-define-execution-order-of-scripts#:~:text=you%20can%20use%20the%20attribute%3A

I like to have in general just one Monobehaviour and the rest are normal C# classes (until you need some prefabs and scripts which do change just one single object) and the main Monobehaviour controls which Update is called first. Anyway you could also use Events for some particular cases.