Where to Start With Manga
The format question
Manga reads right to left, which trips up new readers for about five minutes. The panel order, speech bubbles and even the book spine are reversed relative to Western comics. Most publishers include a brief guide at the start of new editions. It becomes automatic quickly.
The more useful question for new readers is not format but genre, because manga covers more ground than most people expect. The quiet domestic drama of a series like Yotsuba&! has almost nothing in common with the kinetic violence of Berserk, and both differ completely from the existential horror of Junji Ito.
The ones to start with
One Piece for epic adventure: 1,000-plus chapters of pirate mythology that has been running since 1997, but it earns its length through genuine world-building and character work. Start at the beginning.
My Hero Academia for superhero drama with a school structure that makes it accessible for readers coming from American superhero comics.
Your Lie in April for emotional range: a music drama that demonstrates how still images and careful page composition can convey sound and feeling.
Death Note for psychological thriller: tightly plotted, short enough to complete in a weekend, and an introduction to how manga handles interior monologue and dramatic tension.
A note on format
Single volumes are the right entry point. Many manga are available digitally through official apps, which removes the right-to-left adjustment because the interface handles it automatically. For print, most bookshops stock the first volumes of popular series separately.