Whose sheet this is
A section's conduct is really what every teacher saw, not only homeroom. When the adviser keeps subject conduct on — it is on unless they turn it off — each subject teacher gets a Conduct page for their own gradebook: the same grid, the same AO, SO, RO, NO marks, against the core values the adviser chose for the section.
Marking
Pick the grading period and mark what you observed in your own classes. The core values are the adviser's list for the section — rename or extend them with the adviser, not here. Mark as done when the sheet is finished, so the adviser can see it is in rather than merely quiet; reopen it if a mark needs changing.
What prints
Nothing you mark here reaches a card on its own. The adviser reads every subject's sheet side by side on the class Conduct page and settles the one mark per learner per value that the SF9 carries. Where your sheet and another teacher's disagree, that judgement is the adviser's to make — your sheet is evidence for it, kept as you wrote it.
The page is missing
Either the adviser has turned subject conduct off for the section — the pages go with the setting — or the gradebook is not linked to an adviser's class yet, so there is no section list to mark against.