I don't want to use Local Host Multiplayer. And I don't have server.
If you don't want to host locally and don't have a server, how do you expect it to work? I never used Python Flask, but it doesn't somehow magically replace a webserver (how would it!?). It's just another piece of software you can run on a webserver.
What I need to use? Node HTTPREQUEST or Multiplayer ENET?
HTTPRequest (as the name suggests) is for sending HTTP-requests - like your browser does in order to render a website like this Q&A.
ENet is a network communication layer implemented on top of UDP which makes the communication between the client and server reliable and in-order, two things UDP itself doesn't guarantee but are crucial assumptions in many games.