I have many ebooks I have from scouring the Internet in two formats: epub and PDF. I want something server like that lets me drop read them from any device on my local network and remembers where I left the book on device and let's me continue on another. I want the client app to have android and Linux support while the server should run on linux. Is there anything out there?
Bonus points if it autographs metadata from the internet and organises them by topics, authors, ddc etc.
TLDR: An ebook library running on a Linux server with Android and Linux client software.
Sounds like you want Calibre + Calibre-Web! Web has a nice frontend that lets you send to Kindle, or download or just read right there. There are definitely apps that let you link to that library and read the books that way. If you have a different ebook that supports KOReader, even better. You can add your calibre Web
Someone below mentioned Audiobookshelf which is great but it for audiobooks.