The fish adapt fairly quickly to what is in the stream. If there are minnows in the area stocked trout will hit small (size 10 or 12 marabou streamers) in the pools and nymphs or soft hackles in the current seams. Drift you fly on the slower side of the current seam. within a couple weeks of being in the water these fish will be sipping emergers or dry flies

It is awesome that you get to take your dad fishing. Good Luck!