lad vs fella

lad and fella both are nouns.

Word	Noun	Adjective	Verb	Adverb
lad	Yes	No	No	No
fella	Yes	No	No	No

As nouns, lad and fella are synonyms defined as:

Other synonyms of lad include blighter, bloke, chap, cuss, feller, fellow, gent.

lad (noun)	fella (noun)
a male child (a familiar term of address to a boy)	a boy or man
a boy or man