You won’t be walking around the local woods as there are hardly any trees 🙂
We used their OS map equivalents but can’t just put my hands on them (think bought in the UK before we went).
The area around Hveragerdi near Reykjavik has easily accessible hikes that also take in the hot river plus some bubbling mud and steam vents out in the hills.
One thing we didn’t expect was how difficult some of the terrain was. It is very “new” country in geological terms where a lot of loose stuff hasn’t yet eroded, so innocent looking steep descents marked on the map could be slow and a bit treacherous where it was soft and crumbly underneath. Nothing to avoid, but maybe just allow a bit more time or slightly reduce the distance compared to Scotland.