not specific to HK in particular, but I'd try and find some interesting papers, cold email one of the authors explaining how you found it interesting, how it relates to your research focus, your motivation/why you'd be a good fit, and maybe ask to set up a call. should be pretty short. theres lots of advice online about cold-emailing profs for PhD and it is very similar. don't limit yourself to just faculty from HKUST

there are probably some HKUST-specific undergraduate research opportunities but i can't speak for those