How to log in to Twitter from a browser?

Question

JavaScript

Good afternoon
I want to make a button for registering with Twitter
The client, it goes to the window that opens, enters my data
I receive a token, send it to the server, and work with its data from the server
On the JS client
https://dev.twitter.com/ web/sign-in/implementing
Used this API, it was not possible to send even the 1st request, they say CORS, I will not let you
in. I will be glad for any help in this matter