Does this mean read out loud? I've never seen "read out" before and I'm a native English speaker. We generally say "read out loud"
As in "she read out the instructions on the label"?
True, but it does sound kind of weird when you're talking about a letter.
I am also a native English speaker, and I would be more likely to say "Read it out for me" than I would "Read it out loud for me". The "loud" is redundant, when you're asking someone to read it out - they can hardly read it out silently, can they!
If the meaning of "membacakan" is "read aloud to other people", the translation should usually be "read out" rather than just "read".