If you want exact matches and you'll only ever have one match, then this should work:
echo -a Line # $+ $fline(@test,%text-to-find,1) $+ : $line(@test,$fline(@test,%text-to-find,1))
If you want them in variables:
set %linenumber $fline(@test,%text-to-find,1)
set %linetext $line(@test,%linenumber)
Note that if you didn't set %linenumber, you'd need to replace %linenumber in the %linetext section with the code from %linenumber.