Now, 1Gbps is a common LAN for even for Home use. But old laptops lack of 1Gbps NICs. If you want to upgrade to 1 Gbps or add a new LAN card with a USB interface for Linux, same again old issue lack of drivers!.
Following 1Gbps USB LAN card works out of the box on Ubuntu or Debian 10 ( I tested on them so mostly it works on all recent kernels)
AmazonBasics USB 3.0 to 10/100/1000 Gigabit Ethernet LAN Adapter
AX88179 based. Drivers are Kernel included.
So Enjoy! your 1Gbps.