Onde devo colocar as chaves da API do Discourse para que eu possa buscar as postagens?

I’m not sure how you are making your api requests (which tool or programming language), but the api key and username go in the http header.

Here is a curl example from the Discourse API Documentation

curl -X POST "http://127.0.0.1:3000/categories" \
-H "Content-Type: multipart/form-data;" \
-H "Api-Key: 714552c6148e1617aeab526d0606184b94a80ec048fc09894ff1a72b740c5f19" \
-H "Api-Username: discourse1" \
-F "name=89853c20-4409-e91a-a8ea-f6cdff96aaaa" \
-F "color=49d9e9" \
-F "text_color=f0fcfd"
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