I donโt understand why is everybody losing their minds over this.
Unless OP is in his mid or late 20s, I donโt see a harm in talking to a 17 year old girl or maintaining a healthy friendship with them which may eventually turn into something else once they are older.
Once they turn adult, you can see where it can go. And she is 17, not like she is 14-15 that you start talking about pedo and that crap. Also, donโt get physical or anything. If you are interested and find her cute, just be friends for now and tell her you can be friends for a year and then see where it goes (here Iโm assuming youโre in early 20s and single. Otherwise you respectfully decline and stay away because there is less future for that kind of age gap)