1) For the written test, you can make as many attempts as you want to. For the road test, as far as I know, you get to take the advanced road test with 2 years experience and if you pass you get a full license and if you fail, you can still take the basic road test and get a GDL license. A GDL license allows you less demerit points before you lose it and zero blood alcohol.
2) As far as I know, you can in both provinces drive on your foreign license for 3 months after settling. If you are residing in AB, you need an AB license after that and if you are residing in SK, you need an SK license. You can drive in SK on an AB license and vice versa but if you move from one province to the other, you have 3 months to exchange, however no test is needed for that.
3) Depending on which test you pass, you could get a full license or a GDL license.