introduction vs proposal

introduction and proposal both are nouns.

Word	Noun	Adjective	Verb	Adverb
introduction	Yes	No	No	No
proposal	Yes	No	No	No

As nouns, proposal is a hypernym of introduction; that is, proposal is a word with a broader meaning than introduction:

introduction (noun)	proposal (noun)
the act of putting one thing into another	something proposed (such as a plan or assumption)
the act of beginning something new	the act of making a proposal
the act of starting something for the first time; introducing something new	an offer of marriage
the first section of a communication
formally making a person known to another or to the public
a basic or elementary instructional text
a new proposal