Welcome Marvin,

A good starting point is the Query > Ages and Birthdays > Birthdays (all)

That lists the birthdays of everyone where at least the month and year are defined.

To modify the Query to only list those who are currently living you need to understand Rows tab filters.

Have you read the advice about how to build and modify Queries?

With the Birthdays (all) standard Query you must use the cog Query Menu > Save As Custom Query…

Then on the Rows tab add: Exclude unless %INDI.DEAT[1].DATE% is null

That excludes everyone who has a Death date.

Mike Tate