Luxury busesn trains from Penang

I don't find exact locations to take these buses from Penang across Malaysia or to Thailand (including visa runs) or Singapore


Love to get advice on exactly where to go (all I see is Komtar or Ninbong but no specifics) , where to buy tickets , where to board the buses, where exactly it stops eg in Hat Yai, KL , Singapore etc and advice on best timings to take buses for visa runs, where to stay etc


Hope those who have actually done these trips to share their experiences and advice


Another is taking the train from Penang to Hat Yai


Thank you all!