pre-noun adjectival
this sort of; this kind of; like this; such
Refers to something close to the speaker (physically or psychologically), or to ideas just expressed by the speaker. Used before a noun.
こんな本を読んだことがありますか。
Have you ever read this kind of book?
こんなに遅くまで起きているのはよくない。
It's not good to stay up this late.
It's been a long time since it was this hot.
It's inconsiderate to call at a time like this.
This wasn't how it was supposed to be, but the plan failed.
こんな points to something close to the speaker ('this kind of'), while そういう points to something already mentioned or near the listener ('that kind of').
こんな is a pre-noun word that directly modifies a noun (こんな人), while こんなに is an adverb that modifies verbs and adjectives to show degree (こんなに大きい).