This review may change as I continue to read the chapters, I hope that you get this and improve your material to the best of your abilities.
Grammar is bad, there are mistake that change the whole meaning of a sentence, also some bad word selection, the sentences either have additional words or is missing something, of course i don't expect something amazing in wn, but this is definitely a bad side regardless ( maybe english isn’t your first language, neither mine, but there is a lot of apps to correct your mistakes, please do make use of them).
I read the first chapters and I felt kinda boring and cringe at the same time, a lot of unnecessary scenes... details that could be skipped, not much invested in design, but the actions are very detailed, but still, it didn't reveal anything important to the readers in my opinion.
I am fine with mc liking children and all that, there are contracted assassins with morals in real life as well, but what is his reason for liking children that much (if it is in the fanfic then ignore this point) ?
I'm not gonna judge u about the beggars because that's irrelevant to the story, but the fanfic seems to portray that is common for beggars to make part of gangs, which is totally possible, but that's not common my man; Giving 1000$ to a girl is silly as well, even if he was following her, assuming that she "might" participate in a gang is irresponsible action.