Yes and yes!  Gwen has been a full time musician for almost three decades. She was recently performing in Brisbane, and she's playing shows in both Australia and Japan this year.
assitant
I think she’s working on a new album.
assistant
Is Gwen Stefani of No Doubt still active?
user
What do you mean by "active"?
assistant
Does she still perform?  Is she writing new songs?
user