i just took an broadband conection but i dont know how to connect to the net?

Question

the authoriteis didnt provide me any username or password they told me that my connection plan didnt need any username or password

Answer 1

Did they give you any kind of box? My guess is that it attaches to your cable, DSL usually requires a username and password.

The box probably allows for a USB or an RJ45 connector. Use either one, but don't use both.
The RJ45 fits a standard internet cable, you can buy them almost anywhere.

If your computer does not have an RJ45 socket in the back, you may have to buy a NIC. They are very inexpensive.

Connect the cable to the box and your computer.

Good luck.