Is the word these a noun pronoun or adjective?

Answer 1

Yes, the word 'their' is a pronoun, a possessive adjective, a word placed before a noun to describe that noun as belonging to someone or something.

The possessive adjective 'their' takes the place of a possessive plural noun or two or more nouns showing possession.

The possessive adjectives are: my, your, his, her, its, our, their.

Examples:

Jack and Jill live on this street. Theirhouse is on the corner.

The Walkers live on this street. Theirhouse is on the corner.

Answer 2

Yes, when the word 'these' takes the place of a noun in a sentence, it is a demonstrative pronoun.
A demonstrative pronoun takes the place of a noun, indicating near or far in place or time. They are: this, that, these, those.

Examples:
These are mom's favorite flowers.
I would like two of these.

The word 'these' is an adjective when placed before a noun to describe that noun.

Examples:
These flowers are mom's favorite.
I would like two of these muffins.

Answer 3

The word 'these' (the plural form of 'this') is a pronoun, an adjective (sometimes referred to as a determiner), not a noun.

The pronoun 'these' is a demonstrative pronoun, a word that takes the place of a plural noun indicating near in place or time.

Example: I would like some of these, please.

The adjective 'these' is placed before a plural noun to describe that noun as the ones indicated.

Example: I would like some of these tulips, please.