If you would like to make something similar to this Here is an almost 400 paged tutorial on how to design and model a robot https://www.artstation.com/artwork/48Y984
You can buy it here https://www.artstation.com/marketplace/p/XmvyB/380-paged-written-pdf-tutorial-on-how-to-design-and-model-a-robot?utm_source=artstation&utm_medium=referral&utm_campaign=homepage&utm_term=marketplace