Can We Use Articles Before Adjective And Adverb

Of course, we can, but an article is related to a following noun in this case. For example:

This morning I saw a big red and green bird in the tree.
Two cars passed us. The blue one was catching up with the grey one.

An article can also be a part of a whole collocation, e. g.: a little bit, a little, a few, a trifle.

As for articles before adverbs, the example is: a very beautiful girl.