How to Analyze and present predicted and observed data?

In your modell you should have done a single parameter sensitivity analysis as well as a probabilistic sensitivity analysis.The observed data - hopefully - are in the area covered by the probabbilistic sensitivity analysis. If so (and also if not) the sensitivity analyses show you which parameters "move" the results of the model in the direction of the observation. Now you can reevaluate the quality of your parametrization or even of your modelling approach.

If your model and reality are totaly different check the model ;-))

It depends on the questions / field of science you are in. Sometimes scale/granularity of the model has to be adjusted. Sometimes the model misses relevant causal connections.