Could i put
275/40 on my wheels instead of 275/35 just to fill the arch a little more ?
Yes you can and it would achieve what you want it to, but it's not the best solution. 275/40 is a big size and may cause some rubbing on the front wheel arch liner. It's difficult to say without knowing all the details of the wheels, such as width and offset, but a 245/45 may be a better option. This gives you the same sidewall height as the 275/40, but is narrower and helps avoid rubbing at the front.
A 265/40 is another option as has been said above. It'll give you more sidewall height than the 275/35 and fill the arches more, but isn't quite as big as the 275/40 and would avoid the problems you might get with them.
It's impossible to tell wheel width by measuring the width of the tyre and it's really difficult to determine it by measuring the wheel. Alloy wheel "width" is the distance between the inner face of the outer rim and the inner face of the inner rim, so it's impossible to measure accurately with a tyre on. The width will most likely be stamped on the back of the rim, followed by a J, so 8.5J, 9J or something like that.
I would avoid the 275/40 if I were you and I would go with 245/45 to maximise sidewall height and close the wheel arch gap, or go for 265/40 or 255/40 for a compromise between what you've got now and the 245/45 size. It does slightly depend on wheel width, I wouldn't put a 245 on a 9.5 or 10" wide rim for example.
Looking at your profile pic, the wheels look like Calibre Verso, which are 8.5" wide, so, subject to confirmation of that, I would recommend the 245/45. This will achieve the same arch gap closure as the 275/40, but is a much better width for that width of wheel.
