Don’t worry about it 🙂
If anything, the interface is what you should consider “a hub” in your signal chain. It’s the device which transaltes the analog audio signal you produce with your Uke and additional gear and translates it to a digital one a computer can understand and work with.
I threw together a little Flowchart for you which I attached to this reply. This will hopefully clear out any confusion. You are free to feel amused by my highly professional work on this by the way =D
Please note that you can skip the amp part of this entirley should you want to and plug yourself directly into the interface. I don’t do it that way though because I like to use the amp as my first instance for EQ shaping and stuff and also like to hear what the signal I’m going to end up recording will sound like without wearing headphones. Pro tip in regards to Reverb at this point: Some is okay but less is always almost more here.
If you need further instruction or help on anything (especially when you start recording that way) don’t hesitate to ask.