A lot of students, especially Spanish and Portuguese speakers, make the mistake of saying “I have” when talking about age.
In Spanish, you would say “Tengo 30,” and in Portuguese, you would say “Eu tenho 30,” when talking about your age.
The English translation of “tengo” and “tenho” is “I have”, but we don’t use that verb to talk about age.
We use the verb am instead of the verb have.
I have 30 years.
I am 30 years old. I am 30.
In English, we say “I am 30,” or “I am 30 years old”.
We include the adjective old at the end of the noun years.