I install anaconda but I dont know that how install sen2cor
have your tried to follow the instructions given in the Software User Manual on this page?
Yes, I looked but I did not understand how to do it.
Is there tutorial video for the installation and usage sen2cor?
Yes, there are some video tutorials.
Please have a look here: http://step.esa.int/main/doc/tutorials/sentinel-2-toolbox-tutorials/