How can I record the sound of my guitar without a microphone jack?

I'm trying to record the sound of my electric guitar on Ubuntu 20.04.2 but I can't do it since my laptop (Toshiba Satellite Radius 14 L40W-C-102) has only one audio input socket and it works as headphone jack. Though the specification page of my laptop says it is an "external Headphone (stereo) / Microphone combo socket". So, I'm trying to use it as microphone (line in socket in my case) to record sound. When I plug in my guitar to this socket via a regular guitar cable and a 3.5mm adapter, the sound volume icon turns to headphone. How can I use this socket for recording?

The combo jack uses a 4 contact connector (three little rings on the 3.5 mm end) to handle the singals - you can by an adaptor to separate the signals and access just the microphone part.

An alternative would be to get a USB conversion device to connect your guitar in that manner.

Both of these solutions may be less than optimal, but could be worth a shot if your not looking for professional results.