I can't connect to ethernet network
So, guys, I managed to solve the problem. Added the iommu=soft command to GRUB_LINUX_CMD_LINE="". It turns out that I had to disable IOMMU in the BIOS when I installed the system, since being enabled Ubuntu didn't recognize my USB devices. I found this out after running the command "sudo dmesg | grep -i eth" in the terminal and seeing that I had a error message with the network card. I researched and found this solution that I mentioned at the beginning. Thanks to everyone who tried to help!