Octaves

see: https://musescore.org/en/handbook/octave-lines#apply

Measure 78 is going to be a problem applying the 8va to only that note. Since it overlaps with the 32nd notes in time they will be affected by it also. The way to work around this is to put the notes you do not want affected by the 8va in the third voice of the bass clef (I'm assuming the whole note and 16th notes are in voices 1 & 2). I would put the rests before and after them in the same voice. Then select those notes and use ctrl-shift-up arrow to move them to the treble clef. To make it look right, you will need to select the dotted 1/4 note at the beginning of that measure then ctrl-click the 16th note above the 16th rest. If you select only the dotted 1/4 note, the 8va will extend to the end of the measure. You can then double click the 8va in the lines palette. If it looks too long you can adjust it so it only covers the dotted 1/4 note. After that, select the last three chords and apply the 8va to them.

All of the rest of the notes you have marked can be selected and apply the 8va like kuwitt said.