Without exceeding the space available per line, you can type whatever you want, the way you want it. Typical examples are names and/or phone numbers. We recommend checking your design in the preview window to make sure the content is not too long, because font size will decrease proportionally to the length of text. The best typeface for long texts is number 3. This font gives more visibility to the text.
It is also important to keep in mind is that Packs include labels with a single line and others with two, so the text of the second line must be complementary since it will only be seen on large labels that include two lines.