What are the physics principles that are used frequently for being a doctor/surgeon

i lookked on google and there appears to be nothing

Just one example is if you were interested in nuclear medicine, then you'd need a very good working knowledge of the physics underlying nuclear decay and understanding how to work with half lives of radiopharmaceuticals. In order to understand how x-ray machines work and how CT machines are able to generate images of the inside of the human body requires some rather sophisticated physics. Especially to understand how MRI works requires extremely sophisticated mathematics and physics..

There are also many indirect applications of physics in clinical medicine besides this.