Can someone plz explain what the preterite and imperfect tenses ! test

Sure

The preterite is used for actions that started and finished during some defined, limited time in the past, like in the sentence, "He ate his dinner last night." On the other hand, the imperfect is used for actions that were habitual or perhaps did not have a set end point, such as "The kids used to go to brunch every Sunday."   The imperfect is often used as a sort of background information, which contrasts how the preterite is used. For instance, in a story about a man meeting his friend in the middle of the night to chat, sentences concerning the actions of the man or his friend would likely be in the preterite (as they indicate primary information) whereas sentences concerning the setting or other background information would likely be in the imperfect.  

the correct answer would be the first one. " soy jorge de estados unidos, hoy tengo 18 años y puedo vivir en mi casa solo."

explanation:

in the usa you can live alone when you're 18 years old however you can not live in your own apartment when you're 16 years old.