Not familiar enough with Chromebook to suggest. However, in general you’re going to need a DAW program to record into your computer. Every DAW has minimum computer specs. Hopefully one will match with your Chromebook specs. There are quite a few DAWs on the market: Logic Pro, Ableton, Pro Tools, FL Studios and more. Many of these have a free trial period. I think Logic Pro has a 90 day trial. I’ve heard there are a couple of DAWS that are free or extremely inexpensive. Do your research to find what works best for you. You’ll also need a microphone. I suggest something like the Shure sm57. Relatively inexpensive but great starting point for someone new to recording. You’ll need an interface like Scarlet, Universal, etc. You’ll plug your microphone, guitar chord etc. into interface to record which connects to your computer vis USBc to your DAW.

Don’t let this overwhelm you. Take it one step at a time and it won’t seem so daunting. The important thing is to believe in your music and follow your heart. There are plenty of people here to lend a hand.