Well, you could start your search on dedicated manga websites. Some well-known ones are MangaReader or MangaPark. Sometimes, libraries might have digital or physical copies too. Also, keep an eye on official publishers' websites for availability.
I'd suggest starting with copying your favorite manga panels to understand the style and techniques. Enroll in local art classes if possible. And don't forget to study the works of famous manga artists for inspiration.
You can begin by getting some basic drawing tools like pencils and paper. Then, look up tutorials online or in books to understand the fundamentals of human anatomy and proportions.