only jesting about your bonnet Dean . .
get your missus to sit on the front edge of it while you pull the lever, and then stand up while you are still pulling.
Ok . .so once you are in there . .first try and adjust your bonnet pull cable as you are going to have to keep checking the header tank. There is a guide on here somewhere. easy job , just 1 small bolt head to loosen , re tension cable outer & re tighten (see guide)
IF the header tank is below the "cold level" mark it could/ probably is a coolant leak . If the header tank is empty or almost empty , same as above, but that means your low coolant warning is not working as well. (Low coolant warning is normally a problem the other way round , with it showing when level is fine owing to float switch in the tank fubered.)
IF your header tank is still at its usual level , your "white smoke " from the grille area issue will probably be something else & not a coolant issue .
IF the level is down you need to refill to cold level mark & monitor it constantly , after each short trip , over the next few days to see if it drops . IMO short trips are ok . . but nothing more until you find out if coolant is dropping & how quickly.
As a guide my leak was about half a litre every 100/150 miles in use , but would not lose anything while parked up Monday to Friday. Temp gauge was always a steady 90/92 with this leak ongoing.
Report back once you have seen the header tank level & we can go on from there