I live in North Norfolk, and often ride over Suffolk way around Tunstall / SOuthwold area. It isn’t mountain biking territory really, although the Tunstall forest trail is rarely flat, it undulates.
Doesn’t mean there isn’t some great riding to be had if you are into all sorts of cycling. What you do get is lots of very quiet roads, bridleways and byways, so if you enjoy road or gravel cycling, and quiet scenery then it’s not a bad place to live.
I tend to ride the two extremes where i am, either singlespeed gravel bike away from coast, or fat bike on the masses of sandy beaches we have.
Plus whilst you may not become a climbing god, you can get a decent workout as you never really stop pedalling, plus you’ll have the headwinds!