I received a phone call about my unusual activity on my Apple account, is it legitimate?

Scams (e-mail, text messages, and phone calls) are getting very good at closely imitating true Apple communications. Always be cautious. Here are some guidelines:

Recognize and avoid phishing messages, phony support calls, and other scams - https://support.apple.com/HT204759

If you are uncertain about a message and a resource provided in that message, do not click on any links. Try to independently verify the resource by going to a support page on apple.com and use that to contact Apple.

In this case, Apple won't call you unless you ask them to, so this is almost certainly a phishing call.

No. It's not.