Would is a modal verb. Lesson 27 shows you how to make correct sentences with it. This lesson shows you when to use it. Notice that -'d is the short form.
If we hadn't met that time, I wouldn't be here now.
(But we met, so I am here now.)
I think he would find the movie very interesting.
What would you do in my place?
If I were you, I'd take a long holiday.
NOTICE: ALSO must and should (Lesson 33)
They wouldn't have lost if John had been playing for them.
(But he wasn't playing.)
If I'd known you were coming, I would have stayed longer.
(But I didn't know, so I left.)
I'd like some information, please.
want, but it is more polite
Would you like some coffee?
Would you like to join us?
Would you open that suitcase, please, madam?
My car wouldn't start this morning. (Lesson 31)