It means they agree.
By itself, it means "I agree". Within a sentence, it might also mean "you agree", "he agrees", etc., as well as "I agreed", "I will agree", "You agreed", "You will agree", etc.
to agree
I agree.
That would be something like: "I agree with that"
Skip that website. Unless you agree to receive "junk" mail, they will not allow you to proceed. If you really must see the content, select "allow" or "I agree" then put the sender in your junk mail folder so transmissions will be blocked by your mail filter.
Agree deals
true
i agree
like to said yes
i/we agree
Agree; go along with