Hello Rodrigo
There are various ways to show the status of interfaces and each command provides different information and in different formats. The command initially chosen by Rene is the show ip interface brief will show the status and protocol of all the interfaces in a list, so you get a general picture of all interfaces with one command. If any of those interfaces are configured with IP addresses, those are also displayed.
The show interface fa0/x switchport command will show the switchport configuration of a single port in detail. This can be used when the only information you’re looking for is about that port in particular.
There is also the show interface status command which will provide a list of all the interfaces and include a column that shows the VLAN on which they are assigned if they are access ports, or if they are trunk ports, the word trunk will appear in that column. This command shows all the interfaces including the operational mode in which the ports are functioning.
I hope this has been helpful!
Laz