Original score would be 1.6, but I'm leaving it as 3 as encouragement. There are many details that are not well thought out, and it hurts the story. I'll try to keep things to main points, so it doesn't drag too much.
Writing: below average at best, grammar and vocabulary needs more improvement. If possible, you might want to get a proper editor to help you. You often add irrelevant or redundant details to your sentences, eg. Repeating 'excited' 2 or 3 times in one paragraph. Your writing is uninteresting, it doesn't draw in the reader, you tell them what happens instead of showing it. Eg. 'The gun clicks, which says it's empty.' The transition from this to the remaining fight scene is choppy. One way to improve on the fight scenes is to play with the MC's 'body' a bit, toy with the perspectives and add more physical detail to make it more dynamic. Eg. 'He frowned at that click. Empty huh... Daggers then, as he pulled them out from the inventory. MC leapt towards the enemies in one move, and decapitate the nearest assassin with his momentum. It took them a second to orient themselves from his sudden action, and MC exploited that. Another decapitation to his right and he pushed himself off to the one on his left. That one's next.' Don't tell us about the fight, be in the fight with MC, show us how it went, make us feel as if we are him/with him experiencing the action.
Don't write a static scene for us, it feels like MC just took pot shots at stationary targets instead, target 1 here, he stabs, target 2 there, he shoots. 'His heart was thumping loudly, adrenaline was one hell of a drug. He couldn't stop the mad grin crawling up his face as he went after the last one. Pistol out, MC stared at no.10 right in the eye as he pulled the trigger. That shot rang out loudly in the now silent night, "Ding" went his system, as the completion screen popped up in his view. All done before dinner too, perfect.'
Your characters: let's start with MC first, he is a robot. If he does not emote often, then add in more details/adjectives to the times that he does. A shy smile, a devious grin, a sly smirk, burning anger, frustrated roar, gritting his teeth in frustration, murderous rage. That would let readers know more about him, how strong were his emotions on the scale at that point. Charcaters who don't express much emotions tends to exaggerate their emotions more when they do, was that how your MC is like? How worried was he on the scale? Pacing around in circles, biting his lips, staring into the distance deep in his thoughts? It helps in character building so we are not stuck with a blank template of MC. At this point, all I know of him is he has white hair, purple eyes (?), is 17, seems to have almost no emotions.
Your side charcaters are also very unrealistic. The girl just went through a traumatic event, had the MC decapitate a man in front of her, was probably covered in that man's blood together with MC and she just decides that this person could be trusted? Sharing a hotel room, then a bed with him? No night terror? No despair over her sh*tty life? The instant MC appeared, she was cured of all her problems in life. No need for psychologist or anything? The lackey is also the same. They trust far too easily after just experiencing a traumatic event.
Plot: I guess it's going to be a typical xianxia plot then, just need the dumb bimbo harem to appear before everything's in place. I'm not going to expand on my disdain for this trope. Plot convinience, plot armour and mary sue characters are the main flaw for this type of plot.
Please do not make this girl one of his future love interest, otherwise this would be grooming, and that's messed up.
