Does the Blaze template have watcher functionality?

I don’t remember using it again after 5 years.

I’m asking for help because I can’t find it easily in the document.

The problem is the same as the title.

If you want, can just give me a link to that section.

Thank you.

Do you think of the tracker autorun?

I’m not pretty sure either what you are asking for exactly.
But if you are asking for updating UI by changing data on server,
you can just use Collection.find() in Balze helpers after Publications & Subscriptions.
The data will be arrived in client and the data tracking(watcher if you are asking this) will be performed by DDP automatically.