One of the most popular audio interfaces I recommend if you want to record acoustic or electric guitar (or vocals and other instruments) is the Focusrite Scarlett range (link to Amazon for details and different options).
In this example, I’m using an iRig HD 2 (check out my review to see why I highly recommend it for electric guitar) and plugging it into my PC’s USB port. If you don’t have a microphone or audio interface, learn about the different recording options in this guide. You can use an audio interface or a microphone. You have two ways to record a guitar in FL Studio 20. 9.3 Related Guides and Lessons: Step 1: Connect Audio Interface or Microphone