manual button and part numbers

alright we all know my car has a million problems, but one thing thats not a problem im stumped about, i knwo this is a dumb ? im not familar with it though the manual button on my car ok when i push that button and put the car in second it keeps me in second right it wont start me out in first in the snow and ice, because we just got 3 ft of snow here in salem indiana were i lve and the roads are cleared and passable but slick and a fish. and the vavle cover gaskets i knwo ive asked but where do i order them from ima try tightening down my cover in hopes of the working but incase it dont were do i order them and to help out even more lol what r the part number thasnks and sorry for all the qwuestions im trying to get familarized with the wonder of subaru lol

[Earthworm]

The manual button only has an effect with the shifter in "2" or "3". In "D" you will still be starting in 1st gear from a stop.

In "3" you start in 2nd gear but will almost immediately shift into 3rd.