The way it works is the president proposes and Congress disposes.
President Trump can only ask for what he believes is necessary to defend this country. By asking for the money he has stood before the American people, his voters and in effect has said to them,”I am trying to do what I promised I would do too build up our military. It is in the hands of Congress now so all you out their need to let your elected official know where you stand on this.”
Yes, but he has a pen and he has a phone.