How do I say “my favourite person” in Cantonese?
"My favourite person" = "我最喜愛嘅人" /ngo5 zeoi3 hei2 oi3 ge3 jan4/

"My favourite toy" = "我最喜愛嘅玩具"

"My favourite movies star" = "我最喜愛嘅明星"

"My favourite hobby" = "我最喜愛嘅嚐好"

"My favourite son" = "我最喜愛嘅仔/ 我最寵愛嘅仔" 

You can use either 喜愛 or 寵愛 if you have authority over the subject (human only).

Example: 女兒 (daughter), 部下(subordinate), 妃嬪 (concubine), 學生 (pupil)...

You can say: "我最喜愛嘅玩具" but not: "我最寵愛嘅玩具"