Accidentally deleted my Galaxy S6 system file and now there's no more OS.

[AC Question]

I was on twrp and was going to format my phone data. For some reasons I accidentally checked System as well and my OS is gone. The internet connection in my place is too slow to download a 1.6gb Stock Samsung firmware file. What should I do???

PLSS HELPPPPPP

 

[smvim]

If downloading a stock ROM isn't doable at home you need to go somewhere that you can -- local library, nearby community college, a friend with good bandwidth, etc. Without flashing a ROM you don't have many options. Or pay to have your phone repaired at a local phone service shop.