As a general rule, a work permit application for an accompanying spouse is submitted at the point of entry into Canada if the applicants are from a non-visa country. Otherwise, the application should be submitted to a Canadian visa office. For further information, please consult the “Visas and immigration/working temporarily/spouses or common-law spouses” section of the website of the Canadian visa office closest to you (see list).
If you or your spouse wish to study for more than six months, you must first apply for a study permit and a Quebec acceptance certificate (CAQ).
Your minor or dependent children can attend school in Canada if you hold a work permit. Various procedures may apply depending on their age and on whether they accompany you or join you later on, etc. Here is the link for the general procedure.