PofGP 6

We sometimes do not understand that Adam and Eve were only ignorant of good and evil.  Obviously they must have been very knowledgeable for -

"...a book of remembrance was kept, in the which was recorded, in the language of Adam, for it was given unto as many as called upon God to write by the spirit of inspiration;
6 And by them their children were taught to read and write, having a language which was pure and undefiled."  (Moses 6:5–6)

And there is no question that leaving the garden, they were able to sustain themselves and their families.