Hey Lior,
You can import STL and STP files into MATLAB using the fegeometry method from the Partial Differential Equation Toolbox. The following documentation pages details the steps needed to achieve this:
STEP/STP File Import - https://www.mathworks.com/help/releases/r2024a/pde/ug/step-file-import.html
In both cases, the output of the function is a DiscreteGeometry object that can be manipulated as needed. The supported functions of DiscreteGeometry object can be found in the documentation link below: