Adding 3 or more eighth and sixteenth notes without linkage

How can I add 3 or more eighth and sixteenth notes without them always linking together?

As can be seen in the attached file, I am trying to get the groups of 3 eighth notes in the bass clef to look like the 3 eighth notes in the treble clef. Specifically, I want a single eighth note followed by a pair of eighth notes without the 3 of them all being linked together by their stems.

Note that the music in the treble clef is copied from another score. The music in the bass clef is music that I'm trying to score myself.

Any help would be greatly appreciated. I can't find an answer in the Mastering MuseScore School videos.