Help Help, app not installing after placing in system android folder

[Rainielll]

Hi, someone help me. I'm having an issue sa pag develop ng android rom.
Usually kasi kapag nag papplace ako ng apk sa system folder ng ibang android nag auautomatic install naman sya but in my case hindi sya gumagana, maybe its because need ko i edit yung chmod sa android? but i dont have root privilidge sa android version ko so im wondering how can i edit chmod in apk using windows?