llamar vs llamarse
Llamar is to call someone or to name something. Llamarse is to be named. The reflexive 'se' matters.
llamar
To call, phone, summon, or to label someone something.
Te llamo luego.
I'll call you later.
Phoning. Also 'llamar por teléfono'.
Llaman a la puerta.
Someone is knocking at the door.
Llamar a la puerta = to knock or ring. The 'a' is needed.
Me llamó mentiroso.
He called me a liar.
To label someone. Llamar + person + noun.
llamarse
To be called — your name, or the name of something.
Me llamo Ana.
My name is Ana.
Literally 'I call myself Ana'. The standard way to give your name.
¿Cómo te llamas?
What's your name?
Informal. Formal: '¿cómo se llama usted?'
¿Cómo se llama esta calle?
What's this street called?
Works for things, places and animals.
Tricky bit
'Te llamo Ana' means 'I call you Ana' — you're naming someone else. 'Me llamo Ana' means your name is Ana. One pronoun, completely different meaning.