Updating data on form

I have a search page so that when the user selects the project name from the dropdown, they then have the option of either updating that project or creating a new one. i have already created the update/new project page. how do i call that page when they click the update button or new button.

 also, if they click they UPDATE button, when the new page comes up. hwo do i have the fields populated on the results page?

 

any code help would be much appreciated as im stumped.

 

Thank you
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