To make a calculation, you have the following possibilities:
To do this right click at a model, composite model or folder and select 'Run model' or select from the menu _Run, Run all models. You can also use the buttons from the toolbar to run the selected model or all models.
Right click at a composite model in the Project Explorer and select Run model to run all the models within that composite model.
you can also run the current model or all models with buttons in the toolbar