pagestyle{headandfoot}
runningheadrule
firstpageheader{AP Calculus Practice Exam A1}{ Mao Laoshi }{Senior 2}
firstpageheadrule
runningheader{AP Calculus Practice Exam A1}
{ Page thepage of numpages}
{Senior 2 }

footer{}
{iflastpage{End of exam}{Please go on to the next pageldots}}
{}

iflastpage{<text 1>}{<text 2>}

documentclass{exam}
usepackage[paperheight=12cm]{geometry}% just for the example
usepackage{lipsum}% just to generate filler text for the example

pagestyle{headandfoot}
runningheadrule
firstpageheader{AP Calculus Practice Exam A1}{ Mao Laoshi }{Senior 2}
firstpageheadrule
runningheader{AP Calculus Practice Exam A1}
{Page thepage of numpages}
{Senior 2}
footer{}
{iflastpage{End of exam}{Please go on to the next pageldots}}
{}

begin{document}
lipsum[1-7]
end{document}

runningfooter{}{iflastpage{End of exam}{Please go on to the next pageldots}}{Page thepage of numpages}

firstpagefooter{}{}{Page thepage of numpages}