M is closest.
non-living
Since it is one syllable, there can be no other words that rhyme with "nod" and start with the letter N.
No. They are close rhymes, meaning they almost rhyme, but are not exact rhymes. The words that rhyme with swimming would need the letter M in them and the words that rhyme with winning would need the letter N in them.
There's nothing that specifically that rhymes with the letter h.
nation
Pauli
soothe your soul
Nair, nowhere
Nair, nowhere
Lap is a word that begins with the letter L and rhymes with cap.
socks
gnu