>i did some silver gacha and now i have lots of regular soldiers Ns, Rs and even SRs. what should i do with them?
sell the Ns and upgrade the Rs and SRs? at least thats what i read in the chat, but im not sure.

Spam all the silver gacha you can, you won't need silver for anything else for a long time.

Sell the PLAIN N (do NOT sell the unique N). Plain N have (Regular Soldier) on them and they are shown by checking the plain box and unchecking the unique box.

Upgrade the plain R/SR you get to UR. As for uniques, keep all of them that you find, and do NOT use them as fodder except the story girls. You will get lots of unique N story girls from the silver Gacha, like Alette, Lisette, Adelite, Brigitte, etc. Use those characters as fodder for uniques.