I’m pretty sure California is in the United States of America, which a primarily English-speaking country. So no, I would not think it’s important to learn Spanish if you are planning to live in California.

Is it easy to learn Spanish from French? Yes, because they are similar. Spanish, French, English, German are all similar. That’s not to say that if you know one of them, you’ll immediately pick up the others. They have similar words and such, but their grammar and sentence structures are different.

Most people in California speak English. It is always good to learn another language. Spanish and Frendh are both romance languages so there are similarities but the pronounciation is different as well as the grammar.