Both last and latest can be used to mean the “most recent”:
▶️ Did you read the last issue of the magazine?
▶️ Did you read the latest issue of the magazine?
▶️ My last post on the blog got a lot of comments.
▶️ My latest post on the blog got a lot of comments.
▶️ I saw her last Wednesday. (= the most recent Wednesday. We do not usually
use latest with days, weeks, months, or years)
Latest has only this meaning of “most recent,” but last can also mean “final”:
▶️ This is the author’s latest book.
= it is the most recent book; the author will probably write more.
▶️ This is the last book in the series.
= it is the final book; there will be no more books in this series.