It’s quite simple. Create a pocket account at https://getpocket.com
Add some articles or Web Serial chapters to your pocket (easier with the Save to Pocket extension)
Add the Pocket account to your Kobo.
Sync your kobo.
It’s such an under advertised feature of the Kobo devices.
Better but personally I don’t like creating accounts on the kobo, would rather do on the desktop: https://help.kobo.com/hc/en-us/articles/360017763753-Use-the-Pocket-App-with-your-Kobo-eReader
This comment needs to be upvoted to the top.