Translation:Having done the lessons, she immediately went to bed.
Is "Having done HER lessons (...)" also be correct? Or can you only consider "la" as "his/her/its" for body parts?
I think that in this sentence “the lessons” cannot be interpreted as anything else than “her lessons”. As for the EO translation, If you review the “Tips and Notes” section of the “Education” skill you will see that the use of the definite article instead of a possessive determiner is not restricted to body parts, but it can be applied to any personal possession.