It's not very clear what you mean due to insufficient details.

• Are you asking

  Is there a way to access the DOM tree in a web browser from a CGI script written in Perl?

  Then no. Code on one machine can't manipulate a data structure that hasn't even been created yet in another machine.

• Are you asking

  Can Perl be executed as a client-side script in a web browser, and if so, can it access the DOM tree?

  There is software to do that, but it's rarely installed and might only work on Windows machines.

  So unless the client machines are under your control, the answer is no.

• Are you asking something else?