If your TV does not have audio outputs then you cannot connect outboard speakers without modifying the TV. It is possible to use a speaker to line level adapter like this: http/www.crutchfield.com/p_142LOC80/Scosche-LOC80.html
and connecting it to the wires that now go to the internal TV speakers. That would give you a line level audio output for powered speakers and soundbars.
If your TV does not have audio outputs then you cannot connect outboard speakers without modifying the TV. It is possible to use a speaker to line level adapter like this: http/www.crutchfield.com/p_142LOC80/Scosche-LOC80.html
and connecting it to the wires that now go to the internal TV speakers. That would give you a line level audio output for powered speakers and soundbars.