すみません。
すみません。
Sumimasen.
Excuse me. / Sorry.
In Japan, tone matters. A polite phrase can make things smoother, friendlier, and easier. For beginners, polite Japanese is not fancy Japanese. It is practical Japanese.
A beginner does not need to sound perfect. A beginner needs to sound comfortable enough that other people want to help. Polite Japanese does exactly that.