Learn Russian: Вчера эти англичане уехали домой. - Yesterday these Englishmen left for home.

This is a special rule for nouns denoting nationalities or groups of people that end in -анин or -янин in the singular. To make them plural, you drop the -ин and add -е. Since the singular is англичанин, the nominative plural becomes англичане.

Does the word англичане only refer to men, or can it mean English people in general?

While the singular англичанин specifically means a male and англичанка means a female, the plural англичане is used for both a group of Englishmen and for English people in general (a mixed group).

Why use the verb уехали here instead of поехали?

Both are perfective verbs of motion, but they focus on different aspects of the trip. The prefix у- in уехали focuses on the departure and absence (they left and are no longer here). Поехали focuses more on the start of the journey (they set off).

As a quick refresher, why do we use домой instead of дома?