How to create text vertically?

In TextEdit, you can enter text vertically (for languages that use vertical text).

• Choose Format > Make Layout Vertical.
• You can also Control-click in a document, then choose Layout Orientation > Vertical.

In what application? Making us guess won't expedite an answer to your question.

In Pages, you have to enter text in an appropriately sized Text box, and then rotate that Text box.