Cambridge dictionary - https://dictionary.cambridge.org/ru/словарь/англо-русский/journal
"journal" in English can also mean "diary" or "day-book". We even have a magazine titled "The Ladies'Home Journal" - but that's a reference to a woman's personal diary or day-book.
Then there's "The American Journal of Medicine", which is a specialized publication for doctors, scientists, researchers, etc. - a specialized publication which is in magazine form.
But generally speaking, a "journal" is not understood to be a "magazine" in American English.
So, it's a false-friend, mostly.
A "diary" is a set of personal notes which records events and thoughts relevant to one person. The name "diary"is related to the Latin word for "day" - meaning that the notes are written every day, usually in very short passages (a few paragraphs, less than one page).
Often a diary is regarded as very private and confidential. Diary books are sold in the US which contain blank pages, and some such books have a locking mechanism opened with a key.
The usual phrase associated with this process is "to keep a diary" = to write in the diary on a regular if not daily basis.