I was dismissed today after 1 year of employment and they told me they were not required by law to tell me why and I could pick up my final cheque and severance pay on Monday. Is this lawful?

They are not legally required to tell you why, but they have to pay appropriate severance. The company will likely try try to pay you 1 or 2 weeks of severance. You are likely owed 2 - 3 MONTHS of severance. Please give me a call once you pick up your paperwork.
Lior Samfiru