A poem of dynamic words

Question

In many great novels, to the reader I appear
Adjust me, and I describe things that are near

Once more, and my meaning changes only slightly
Again, and you excercised your free will, rightly

Yet another, and I'm something we all ought to do
Again, I'm a boundary with a beautiful view

Again, I'm a place to which many must go
And again, I'm a thing wise men shouldn't throw

Now behead me, I'm a thing you must watch while you speak
Your next action depends on the word that you seek:

Behead me once more, and my use is widespread
Or instead take my foot, of hard things I am said

Answer 1

In many great novels, to the reader I appear

Great novels have a very compelling theme.

Adjust me, and I describe things that are near

Would you perhaps be referencing these, over here? (m -> s)

Once more, and my meaning changes only slightly

Or perhaps you mean those? (e -> o)

Again, and you exercised your free will, rightly

If you exercised your free will, you chose something. (t -> c)

Yet another, and I'm something we all ought to do

I thought this was share, but it turns out we should all do a chore once in awhile. (s -> r)

Again, I'm a boundary with a beautiful view

Especially beautiful at sunset or sunrise, this references the shore. (c -> s)

Again, I'm a place to which many must go

If you need to buy something, you have to go to the store. (h -> t)

And again, I'm a thing wise men shouldn't throw

If you're wise, you will throw no stone. (r -> n)

Now behead me, I'm a thing you must watch while you speak

I know I've heard this from my mother: you better watch your tone! (goodbye, s)

Behead me once more, and my use is widespread

The number one is a pretty widespread number, I'd say. (goodbye, t)

Or instead take my foot, of hard things I am said

That thing must weigh a ton! (goodbye, e)