Can you provide any source?
Yes, from the exit poll:
sonar.wyborcza.pl/sonar/7,156422,25304241,wybory-2019-koalicja-trzyma-sie-tylko-dzieki-mlodym.html
For the sake of making it easy to quote:
18-29 - KO/PSL/Lewica (52%) / PiS/Konfederacja (46.4%)
30-39 - KO/PSL/Lewica (53.3%) / PiS/Konfederacja (45.1%)
40-49 - KO/PSL/Lewica (53.9%) / PiS/Konfederacja (45%)
50-59 - KO/PSL/Lewica (45.4%) / PiS/Konfederacja (53.8%)
60+ - KO/PSL/Lewica (42.7%) / PiS/Konfederacja (56.7%)
It's a fascinating look at how Polish politics are played out - probably older voters rely more on TV (hence ~80% going to PiS/KO), while younger voters are much more internet savvy and able to decide for themselves, resulting in the vote being effectively split 4 ways.
There was some data somewhere showing that the youngest voters went heavily to Konfederacja and Lewica, but I don't remember where I've seen it now.