F9 prints and Shift + F9 shows the preview instead. A bill has to be saved before it can be printed — printing an unsaved bill would put a number on paper that no record holds.
Settings → Company profile lets you pick the paper format — A4 or A5, portrait or landscape, or a thermal roll if your trade defaults to one (restaurants, for instance). The bill reflows to fit whichever you pick; nothing is cropped, it is measured to fit that paper.
Settings → Bill format designer lets you show or hide optional columns (batch, expiry, HSN, discount), add your logo, signature and payment QR, and choose colours and type size. Five fields — description, quantity, rate, amount and serial — can never be hidden, because the law requires them on every tax invoice.
After saving a bill, press "Save & WhatsApp" — or open any saved invoice and use the WhatsApp button. It opens WhatsApp with the bill’s details already filled in as text; there is no picture attached and no per-message cost, because it goes through the ordinary wa.me link rather than any paid API.
Press Alt + A in Aned Book and ask in your own words. It runs on your own computer with no internet and no account — these pages are that same help, published so it can be found before you install anything.