how to have 7zip as my default

when i go to install oq it always comes up as open with curse as my default how do i make 7zip my default

how do i find which folder it is
 

how do u uninstall oq

no matter what ive downloaded the 1.8.2 version and extracted it and 1.7.5 still shows up i want oq gone then maybe it might work how do i uninstall it