Is likewise a pronoun

No, the Word 'likewise' is an adverb, a Word that modifies a verb, an adjective, or another adverb.

Example: Mom was pleased with my effort. Dad likewise expressed appreciation.

A pronoun is a Word that takes the place of a noun in a sentence.

Example: Mom was pleased with my effort. She told dad what I had done. (the pronoun 'she' takes the place of the noun 'mom' in the second sentence)