looking for a j/kdrama or movie where meeting father/mother for first time 

or a half sibling ty

Boarding House #24 - sitcom kdrama - father is looking for his lost child among 6 possible candidates. So that child also meets its father. :)

House of Bluebird - quite long family kdrama - FL meets mother and sister

Kakko no Tamago wa Dare no Mono - mystery family jdrama. The title says everything. :)

Your Name Is Rose (kmovie) - daughter meets her father