Demo support

[nht9499]

import {retext} from 'retext'
import retextPos from 'retext-pos'

Where can I install these packages, I can't found it in readme. Please let me know

[ChristianMurphy]

Welcome @nht9499!
There are several ways to install, they are listed in the readme of each project under the section labelled "install".
https://github.com/retextjs/retext/tree/main/packages/retext#install
https://github.com/retextjs/retext-pos#install
Give them a try in the project directory where you want to use retext.