
Song Gi Tae(20) ,was on a date when someone suddenly grabbed his arm & he black out only to open his eyes in a strange room without one of his legs
https://www.mangago.zone/read-manga/a_room_without_space_side_story_1/
Pi Bada has been struck in a horror survival game with a mysterious killer on a killing spree ..Every time he gets killed in the game its restarts from the beginning once again like an infinite loop ...But after restarting again he realized that Nam Doho whom he only considered as one of the game NPC is behaving differently than before ..
https://www.mangago.zone/read-manga/dreadful_night/
I love this!
https://www.mangago.zone/read-manga/the_promise/
Not a bl but it is SOOO GOOD!!
https://www.mangago.zone/read-manga/survive_romance/

I have full on military ones, here it is.
Over run is wonderful, is one my favourites:
Dio has a long-time crush on his superior, Aidan. He thinks of leaving the army when he becomes a sergeant, as he has decided to ever since he joined the special forces, but in the hopes of having even just memories, he musters up his courage then confesses and has a one-night stand with Aidan.
https://www.mangago.zone/read-manga/overrun/
Stranger in the mirror, I haven't finished it, heard that it had to be wrapped up quickly at the end because of harassment towards the author, but it goes with your description, so I'll leave it here:
Set in the future where AI androids are a part of the society which are used on various fields .. XBT-512087 is an AI android who will be enlisted in the military to work with Reung Deungun(33),lieutenant commander who suffers from PTSD after loosing all his teammates during a certain mission ...
https://www.mangago.zone/read-manga/stranger_in_the_mirror/
Hope it helps!
preferably bl....like military, post-apocalyptic vibe with some action....doesn't matter if there's smut i just want smth to read