What is the ruling on wearing the hijab, and what is the ruling on wearing it if it is colored? And is placing a pin (brooch) at the front to secure it considered adornment?

If the headscarf meets the conditions of the Shariah-compliant hijab, meaning it is large enough to cover the shoulders and chest, does not describe the limbs, and is accompanied by a 'ghishwah' (veil) that covers the face, then it is permissible to wear it. As for the "brooch," it is an adornment, so it should not be used; instead, an ordinary pin should be used.