Remember that the verb querer can look different in certain forms, with its e changing to ie (like yo quiero and tú quieres). Tener does the same thing!
¿Cuántos años tienes tú?
How old are you?
But tener also has a special yo form: tengo!
subject
verb(tener)
yo I
tengo have
tú you
tienes have
él / ella / usted he / she / you
tiene has / have
nosotros / nosotras we
tenemos have
ellos / ellas / ustedes they / you all
tienen have
Remember, in the nosotros / nosotras form, the e doesn’t change.
¡Tengo hambre!
Tener is often used in expressions where we use to be in English.