The closest English equivalent depends on the context:
* If you're talking about possession: "I have"
* If you're talking about a state of being: "I am" (e.g. "Tengo hambre" - "I am hungry")
* If you're talking about an obligation: "I need to" (e.g. "Tengo que ir al trabajo" - "I need to go to work")
It's important to consider the context to choose the most accurate translation.