Perhaps you'd like to try select to speak:
To have only part of a page read to you:
1. Click your account photo or press Alt + Shift + s.
2. Click Settings Settings.
3. At the bottom, click Advanced.
4. In the "Accessibility" section, click Manage accessibility features.
5. Under "Text-to-Speech," turn on Enable select-to-speak.
6. To select what you’d like read to you, on your keyboard, press and hold Search Search. Drag the pointer over a word or area of the screen.
7. Your Chromebook will read the section aloud and each word will be highlighted.

You can read more here: https://support.google.com/chromebook/answer/177893#selecttospeak