I'm confused which to use...

Are you agree?
Do you agree?
You agree?

They all seem to be the same. Help please

Thank you!
1-- Are you agree?-- Bad English. However, we do use 'Are we agreed?'

2-- Do you agree?-- Good English

3-- You agree?-- Short, casual form for #2 ('Do' is just omitted.)
Thank you, Mister Micawber!
With forms of the verb BE, the main verb should end in ing or it should be the past participle.

I am agreeing with you. (You can't use the past participle with "agree.")
I have been agreeing with you.
They were agreeing with you.

The window was broken.
The plans were changed.

With forms of the verb DO (do, does, did, don't,doesn't,didn't), the main verb is in the simple form, which means it is taken from the infinitive with the "to" removed.

to go = go (simple form)
to see = see (simple form)

Do you agree?
Did they agree?
Don't they agree?