GUI tools hide the details. To understand the network, you need raw output.
1. Dog (The new Dig)
dog is a modern alternative to dig with support for DoH and DoT.
dog google.com A AAAA --https @1.1.1.1
2. MTR (Ping + Traceroute)
mtr shows you packet loss per hop, allowing you to identify exactly which router is dropping packets.
3. Nmap (Network Mapper)
Excellent for checking open ports when you suspect firewall issues or ISP port blocking.