These first few lessons are revision of the multiplication amd division that you learned in Year 4. You decide whether you think it would be useful to go back over it. Remember, it doesn't matter that it is labelled as 'Year 4.' All that means is that is when it was introduced. Sometimes it helps to go back a step in order to feel confident enough to move forwards.
These next few lessons are ones that we covered in Year 5. Again, pick and choose what is useful for you.