Yep, just to count how many takeoffs/landings you did. If you take off from A and land at A/B/C/Wherever (during daylight) and that's all you do then put a "1" in each of the day takeoff and day landing columns.
Page totals are the totals hours added up on that page.
Totals forwarded are the total hours you have added up from previous pages.
Totals to date/Grand totals I haven't seen separated before. Both sound to me like they would be used to add up the hours from the current page onto the hours from all previous pages.
Have a look in the front few pages (or maybe the back few) of the logbook, as often there are instructions.