１０課から始めましょう。

one; best; first; foremost; beginning; start; bottom string (on a shamisen, etc.)

circle (sometimes used for zero); 'correct' (when marking); symbol used as a placeholder (either because a number of other words could be used in that position, or because of censorship); period; full stop; maru mark; semivoiced sound; p-sound

lesson; section (in an organization); division; department; counter for lessons and chapters (of a book)

from (e.g. time, place, numerical quantity); since; from (originator); by; because; since; out of (constituent, part); through (e.g. window, vestibule); after; since

to start; to begin; to commence; to initiate; to originate; to open (e.g. a store); to start up; to establish (business. etc.); to start ...; to begin to ...