CAD has a number of features to help design engineers with manufacturability. In Fusion, take a look at the Inspect panel - you'll find analysis tools that will highlight areas on your geometry that might have insufficient draft to release from a mold, or areas that might be difficult or impossible to access with a milling tool. With the right extension, you can set EDA-style design rules for injection molded parts.

There are a number of software packages dedicated to design analysis for injection molding, although the price is far out of reach of hobbyists.