Are there public cultural centers in Poland?

Sth like a chitalishte? In Bulgaria it's a public institution and building that fulfills several functions at once, such as a community centre, library, and a theatre. It is also used as an educational institution, where people of all ages can enroll in foreign language, (folk) dance, music and other courses. In this function they could be compared to the folk high schools of Northern Europe.

Lots. There's a particularly good one in Kielce (WDK) and lots of smaller ones, depending on the policies of the local authority..