The verb heißen is used to introduce oneself.
Informal dialogue:
Ich heiße Jakob. Wie heißt du?
Ich heiße Mia.
Formal dialogue:
Ich heiße Jakob Schneider. Wie heißen Sie?
Ich heiße Mia Huber.
This verb can be a bit tricky for English speakers, since in English we only use expressions like "My name is John Sample" or the verb "to be" to introduce ourselves.
In German, you can use those expressions too:
My name is John.Mein Name ist John.
I'm Simone.Ich bin Simone.
*I'm called Celine.Ich heiße Celine.
(*literal translation)
This is how to conjugate heißen:
Even though sie and Sie sound the same, Germans do have a way to distinguish those: conjugation!
Wie heißen Sie? → What is your name? (formal)
Wie heißt sie? → What is her name?
It's easiest to learn this as a phrase, as it isn't the same as in English. You'll get the hang of it so quickly, since it's used all the time :)