This is pretty basic, but for reference, here's how to add and use FX channel tracks (or send tracks). I'm using Cubase 9 but I'm pretty sure they've been around way before that.

• Add a new FX channel track. You'll be prompted for some info: number of channels, what effect to put on it, etc. All pretty self-explanatory. Highly recommended to give it a clear name (i.e. "Reverb"). The last select allows you to choose whether you want to create this channel inside a folder (which Cubase names "FX Channels") or outside.
• Adjust the effect. With the newly created FX channel selected, go to "Inserts" in the Inspector where you'll see the effect you chosed in the first step (if you did). Edit its parameters at will (the "e" icon, as usual). Note that you can add multiple effects to a single FX channel.
• Use it in the desired tracks.
  • Select the audio track or instrument track that you want to run through this FX channel.
  • In the Inspector, open the "Sends" block.
  • Click one of the empty slots. You'll see a popup window where you can choose what to send, including any FX channels you have created previously.
  • Once selected, the FX will be inserted into that slot with a few controls: a of/off button, a pre/post fader button, a drop down in case you want to swap to a different FX, and below these buttons, a bar where you choose how much of that effect you want to add.