Need help making wp-signup.php fullwidth and with no next button

Hello i am looking to get my signup page fullwidth (without the sidebar) and also would be awesome if i could make it to show all fields on one page.

The Gimme a site and Just a username please could be placed at the top of the page so that is the first thing the users choose. Based on that selection the signup form shows the fileds required for that type of registration.

I add here 2 screenshots of the page.