If you’re not getting audio, may I suggest that you first check the connection to your audio interface, physical and software based.
Does your interface support ASIO? If so, then look across the menus at the top of the screen for one named ‘Device.’ Click on this and select ‘Device Setup.’ Look for ‘VST Audio System.’ If you don’t see your interface, have you installed the drivers and checked that the connections are secure. Check again. If your device doesn’t support ASIO, select ‘Generic ASIO Device.’
On the right-hand side is a drop down list. Select the driver for your audio interface device here. Then select ‘VST System Link.’
On the right-hand drop down list under ASIO input, select the first two inputs for your audio interface device. Do the same for the ASIO output drop down list. Click OK.
Press F4 and see if your audio interface device has been selected as source. Decide how many interface inputs you require. And if you require mono or stereo inputs. If the default inputs are not what you require, right click on them and select ‘Remove Bus [whichever].’ Do this until the ones you don’t want are gone.
Then click the ‘Add Bus’ button and select how many inputs you require. If all mono, simply select ‘mono’ and the number required. When you are satisfied, click on the Output tab.
Select the stereo out for your audio interface device. Click on the ‘+’ sign beside the ‘Presets’ drop down menus and name it as you choose. Press F4 again to close this section.
Click on the Edit menu and select New Project. Choose Empty. Press F4 again. Make sure that the inputs and outputs are as expected. If not, click the ‘Presets’ menu button and select the one you previously saved. Press F4 again.
Add an audio track and record enable it. Hit Record and keep an eye on the wave graphic. If it’s difficult to see the graphic, pull down the audio track and raise the left facing arrow on the extreme top right of the recording screen.
Hopefully, this will get some audio recorded for you. If not, come back here and describe your setup and the steps you have taken to record some stuff. And remember that YouTube is your friend. Just type Cubase and your version. There’s a lot of stuff out there. Good luck and welcome to Cubase!