In InDesign
- When the Missing Fonts dialog opens, tick fonts available from Adobe Fonts and click Activate.
- For other fonts, click Find Fonts, or later choose Type > Find/Replace Font. It lists every font in the document, marks missing ones, and lets you replace them.
- Text in a missing font is highlighted in pink until the font is installed or replaced.
To activate Adobe Fonts by itself, turn on InDesign > Settings > File Handling > Auto-activate Adobe Fonts.
In Illustrator
- In the Missing Fonts dialog, ticked fonts are available from Adobe Fonts. Activate them, or replace the others.
- If you closed the dialog, choose Type > Resolve Missing Fonts.
- To swap one font for another across the document, use Type > Find/Replace Font.
Illustrator > Settings > File Handling > Auto-activate Adobe Fonts activates them in the background. Adobe Fonts must be turned on in the Creative Cloud app.
Install the font with Font Book
If you have the font file, double-click it in the Finder and click Install. Font Book checks it for errors and duplicates. Then reopen the document. Adobe apps no longer support PostScript Type 1 fonts, so an old Type 1 font shows as missing even when it's installed. Use an OpenType version.
Fonts in a PDF
In Acrobat, choose File > Properties and open the Fonts tab. Each font should say Embedded or Embedded Subset. A font without either isn't in the PDF, and the PDF looks different on a Mac without it. Export the PDF again from the original file with the fonts installed.
The faster way: Caretaker
Caretaker shows the fonts an Illustrator, InDesign, Photoshop or PDF file names, and which of them aren't on this Mac, for free and without opening the file. It also finds duplicate and broken fonts and keeps one copy.

Questions
Why does InDesign highlight text in pink?
The text uses a font that's missing, and InDesign is showing a substitute. Install, activate or replace the font.
How do I see which fonts a PDF uses?
In Acrobat, choose File > Properties and open the Fonts tab. It lists every font and whether it's embedded.