The term of validity of the patent right is easy to inquire. Just look at the "application date" column on the front page of the patent document. The protection period of invention patents is 20 years from the date of application, and the protection period of utility model and appearance patents is 10 year. I'll cut a picture to show you the location of the application date:
The red circle is the filing date of the patent, which means that the patent right is valid until March 28, 20 19.