The Italian word il biglietto has a range of meanings in English:
A ticket: At the station, airport, museum, theatre etc.
A note: A letter or piece of paper or card; a short message
A bank note: A bill for 10 or 20 euros and so on
A card: for birthdays, weddings or anniversaries for example
Some variations are:
Biglietto da visita: Business card
Biglietto di andata / ritorno: Outbound / return ticket
Biglietto di ingresso: Entrance ticket
Biglietto intero / ridotto: Full price / reduced price ticket
The verbs to use when talking about buying a ticket are:
Comprare
Fare
Acquistare
And don’t forget to validate your ticket at the machine beforehand, the verbs for this are:
Obliterare
Timbrare
Convalidare