"He has not had many chances in his life."
Translation:Li ne havis multajn ŝancojn en la vivo.
It's a pretty common feature of Romance languages, to add the definite article before a noun, which can show one of two things:
1) Generality - To reference the thing not in any specific way, but in a general sense, for example: "La vivo estas bona." for "Life is good."
2) Implied Possession - It's common to use "la" instead of a possessive pronoun when possession is implied or otherwise shown. - "Li rompis sin la brako." for "He broke his arm." This works with family members as well. - "Lasu min demandi al la patro." for "Let me ask (my) father."
There's no "should" about it.
Esperanto has the compound verb forms available for greater precision, but very often, just the simple ones are used.
Then present is used for both English simple present and present continuous; past for English simple past, present perfect, present perfect continuous, and past continuous (and sometimes even for pluperfect, especially together with an appropriate adverb such as jam); and future for English simple future or future continuous.