how far around is it to walk?

I don't think that you can walk around the lake, but the park might take 20 minutes so, depending on your speed and the route you take

You can walk around the park and up to the south end of the lake.

It has alot of walkin space though it is a big park. But in federal way alot of houses on lakes prohibit this

There is plenty space to walk in the park, not around the lake.

You can't really walk all the way around the lake, if that's what you mean. There are a lot of houses on the lake.