inferences on deterministic models

Hello, Please let me know if I am posting in the wrong place. Thanks

I am working on a project where I have a mathematical epidemic model and I have some data. I want to use statistical methods to find the model that best fits the data.
So I have a very deterministic model and need to maybe use a stochastic approach to finding inferences about the data but I am wondering if anyone has any suggestions as to how I would do this.