Foundation calculation

I am looking for help with the foundation calculation for a small concrete terrace ,it measures 6.5 m x 1.6 m and with a little cantilever due to the sloping ground.I am not sure what type of foundation is required, so I need guidance from an expert. It will be connected to an existing retaining wall ( built 15 years ago) After 2 m from the wall the ground drops away significantly down about 2.5 meter’s.If you have specific requirements and constraints in designing the right foundation for this project, I would be happy to discuss them with you. If you’re an experienced professional in foundation calculations .Please see photos . Thank you for your interest!