be big fan of 是某人/某事物的狂热粉丝
If you are 【a fan of】 someone or something, especially a famous person or a sport, you like them very much and are very interested in them. 狂热爱好者
I am a big fan of Wu Yifan(Kris).
be crazy about 着迷于，狂热爱好
If you 【are crazy about】 something, you are very enthusiastic about it. If you are not crazy about something, you do not like it. 着迷的
Jack is crazy about video games.
be into something 对某事很有兴趣
If you are very interested in something and like it very much, you can say that you are into it. 对…很感兴趣
Marry is very into music.
She is kind of into you.
If you're a Billy Crystal fan, you'll love this film.
I am a great fan of rave music.
He's still crazy about both his work and his hobbies.
I'm into electronics myself.