I'm not sure who this is for.
It's a harem book, and a pretty bad example of the genre. The protagonist has two women propose marriage to him on page *45*. No build up beyond one of the two indicating she thought he was hot 10 pages earlier. No romance, just wham, straight to group marriage.
Readers of harem books, particularly ones that don't bother establishing any kind of emotional relationship, want descriptions of sex. There's none of that, just "we had enjoyable nighttime activities." The author is disappointing both readers of "guy has lots of sex with hot women" audience and the rest of us who like actual relationships. It's like this group marriage is just a way for the author to keep score.
This appeared to be a book about a guy with modern scientific knowledge dropping into an early industrial society. Those are always fun, though this one is badly written. Modern engineering knowledge doesn't transfer to practical knowledge of steam engines. I could draw you a diagram of the internals of a steam locomotive, but understanding the general principles doesn't mean I think I could build one. It's specialized knowledge.
That rapidly goes out the window when his abductor / helper alien lifeboat informs him it's repairing a full sized alien spacecraft, complete with FTL drive. Oh, and he makes ansible contact with authorities on Earth at the same time. Clearly the it isn't, after all, a "lone protagonist struggles to make his way in a primitive society with only his advanced knowledge to help him" book, either.
I'm not sure what direction it took from there, because that's where I stopped reading.