ボートやゴンドラの漕ぎ手って英語でなんて言うの？

>A oarsman.
a rower, especially as a member of a racing team
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>A gondolier.
a person who propels and steers a gondola.
#propels=drive or push something forwards
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An oarsman is a person who rows a boat, especially in competitions.If it more than one person rowing the boat we say "oarsmen".

A person rowing a boat is called an 'oarsman' and this seems to be regardless of gender.
Someone punting a boat - which means pushing the boat along with a long pole pushing on the river bed
- is called 'a punter.'
In Venice the people controlling the gondolas are called 'gondoliers.'
If you have a rowing boat or moror bot, the person controlling the rudder of the boat (if there is one) is called the 'helmsman.'

When talking about rowing a boat the term is an oarsman but when talking about the person who rows a gondola this is called a 'gondolier'

A sculler is a person who rows a boat by moving one or two oars either over the back end of the boat or over the sides of the boat.

An oarswoman is the woman who is rowing the boat, normally with one or two oars and the oars are placed on one or both sides of the boat. The plural is oarswomen.

An oarsman is the man who is rowing the boat. The plural is oarsmen.

For example, native speakers might say "the oarsman pulled hard to gain the lead over his opponent toward the end of the race and win the Olympic gold medal for France" when referring to the person who rows in sport, or "the oarsman gently rowed his boat around the coastline while admiring the cliffs from a distance" when referring to the person who rows for recreational purposes, or "the oarsman rowed the boat down through the canals of Venice much to the pleasure of the tourists who were on vacation in Italy" when referring to the person who rows as a profession.