You take it at a Dutch embassy or consulate before travelling. It is not the same as the domestic inburgering exam taken after arrival in the Netherlands.
Speaking, reading, and KNS must all be passed. They can be sat on separate occasions if needed.
The exam tests Dutch at A1 level. A1 is the entry level of the Common European Framework of Reference (CEFR). It means basic comprehension of simple, familiar words and phrases, not conversational fluency.
For most applicants this means learning Dutch from scratch, or close to it. The official study material is the Naar Nederland workbook and accompanying resources, which define the vocabulary and topic scope.
Generic language apps cover broad Dutch but not the vocabulary, format, or society content the BIB tests. The KNS pool is 100 fixed questions. The speaking pool is published in full.