Redirecting URL with DNS

[Blandinherve]

Hello,

I have a  web server with a DNS server. We have serveral domain names, for
example www.a.com and www.b.com.
I would like to do the following thing : when someone click on www.b.com,
the DNS redirect to www.a.com. And the client would have in his browser
www.a.com
So, is it possible to do that within a DNS server, othrewise, how should I
do that ?

Thanks for your help,

Herve.