Hi @Fayv76 ,
You can download the OpenSignal app to see what the average measured speeds and latencies are in your area. You can then pick the combination of highest bandwidth, and lowest latency to obtain a Pay As You Go SIM for those networks to check tethered and hotspot behaviour using a mobile phone, including visiting fast.com and speedtest.net.
For general home usage, you want to see better than 25 Mbps download at all times of the day, at least 10 Mbps upload, and lower than 30 ms unloaded latency. When it finally comes for the decision to move from wired broadband to 4G LTE internet access, it's somewhat a leap of faith as there are no strong guarantees. Most people make the move when for a particular property, the wired broadband is so atrocious that 4G LTE cannot conceivably be worse.
For convenience you may wish to go for a service provider device locked to their network. Advanced users would probably prefer to take SIM-only (typically phone SIM better than data SIM) and separately buy a mobile router (ideally Netgear MR1100 or better, as judged by reviews).
I guess top tips include to make sure the 4G LTE router has at least one gigabit Ethernet port (if exactly one, you may need further devices such as a switch or powerline adapters with multiple gigabit ports to connect further wired devices for better latency), and to ensure your 4G LTE router can operate without a battery inserted (non-issue with mains-powered).
