Hey! To say "I like" You can either use "main pasand karta hun(karti in your case)" Or "Mujhe pasand hai" Both of these mean the same thing, and as you can see the 2nd one isnt using karna at all, so when using mujhe you basically drop the karna
"yeh pasand hai" basically is "apko yeh pasand hai" with the apko dropped. When Hindi is being spoken alot of the time the subject is dopped, for example "kya kar rahi ho?" This means "what are you doing" as you can see the "ap/tum" has been dropped, because its not really needed to understand the sentence, as "rahi" means female, and "ho" means you.
Anyway hope I didnt ramble on too much!