very basic question - embarrased to ask but I've spent hours looking for the answer

working in eclipse - doing java
I see that in Project properties code templates they use the notation
/**
* ${tags}
*/

I understand that somewhere I can define the substitution variable tags and it would thus be substituted for me

also - in looking at oracle doecumentation I see
can I use that syntax in eclipse - and again how do I invoke it?

I have spent hours trying to find where I define tags .. etc.

Also - when I type @author .. etc .. is there a way that it will automatically expand to some predefined value?

thanks in advance

Dick