Here's why:
* Educate is a verb: It means to teach or train someone.
* Educated is an adjective: It describes someone who has received a good education.
Here are some examples:
* Verb: The teacher educated the students about the solar system.
* Adjective: She is a highly educated woman.
There is no noun form of "educate" in standard English. While "education" is a related noun, it has a different meaning.