What is the difference between is and does?

Excuse me, could you please clarify the distinction between "is" and "does" for me? As I understand, both are commonly used verbs in English, but I'm having difficulty grasping how they differ in their usage and meanings. Specifically, I'm curious about how they're used in sentences and whether they have different grammatical functions. Could you provide some examples to illustrate their differences? Thank you in advance for your help.