Many learners think that these two words mean the same. But the fact is that they have a different meaning.
Borrow means to take something from someone with an intention to return it.
•Can I borrow your book?
( not can I lend your book?)
•He used to borrow a shirt from me.
You borrow something from somebody.
Lend means to give someone something with the hope of getting it back.
•I lend my bicycle to Nadia.
•Lend me your pen for a minute.
You lend somebody something.