I too am struggling with the 2021 revised form - Step 3, chart A. It is not intuitive (and the fault there lies with CRA, QuickTax simply copies it).
However, I do not get any "clickable" names on the desktop version, but notice that chart B instructs "enter the name..." in the singular. So I am using one line per person and dividing up the costs of each trip in columns 3,4 and 5 amounts accordingly (and it quickly fills up the form). For me, two people taking two trips use four lines.
