Many, but not all, models on the site are built to be dynamic to hold period. Even then, most models on A.CRE don’t accomodate analysis periods beyond 10 or 15 years. If the model isn’t built to be dynamic to hold period, or the maximum analysis period is less than your needs, you’ll need to customize to suit your purposes.
You can either customize the model yourself, or hire someone to make the customizations. If you need customization help, read here.