Is it possible to find the ip address of someone who send me an email?

Is it POSSIBLE? Sure anything is possible. But, since you do not understand what an IP address is, then you are not going to be able to find what you want to know. An IP address is NOT a physical address of a computer. It is a (usually, except for static IP, which makes up less than 5%) a temporary routing address. So, if you did find the IP address, someone else would be using that IP address in a month, or less.