Add buttons on the fly

I would like to add two buttons on a page form infomation confirmation, however, the html code in php nest can not be known by browser if I put <form xxxxxxx> <input xxxxxxxxxx> </form> into there. Besically, there is a mail form to enter iterm infomaiton, if it exist before, prompt its iterm id., if it is new, query a next available inerm id for it, then, show a page to ask such as, "do you accept this id?", two buttons below this question, yes and no. Is there any fountion in php which can make it? Thanks.