Take a ready-made template — blog, portfolio, catalogue — or define your own entry type. Either way you get a form, a listing and subpages for it.
Say you show off your projects. Each has a name, photos, a client and a date. You lay that out once from more than a dozen field types — text, rich text, number, date, select, images, file, relation, toggle.
Adding the next project means filling in ready-made fields, like a questionnaire. There is no blank page where the layout has to be rebuilt from scratch.
Add 42 entries and you have 42 finished subpages with their own addresses and sitemap entries. Google sees each one separately.
A restaurant menu, a machine catalogue with specifications, a training calendar, job openings, a list of branches, a Q&A base.