Hi Bing VW and welcome.
As you can see, there is always helpful advice from fellow Mk8 GTI owners within the posts. Enthusiasts with just about every issue with the Mk 8 covered; better advice here than from some VW Dealers IMO!
Another source of advice {well I think so} is the Volkswizard You Tube channel. Apologies if you are already aware, but if not have a look.
He purchased a Mk8 GTI Clubby a few months after me early 2021. His videos covering ownership, tips and advice lasted the length of time he owned the car which was almost 3 years.
Good luck and happy motoring.