good for you in starting on a new plan - questions are always good as they keep everyone on their toes and remind us all what we should be doing.
I have only been on this plan for a week, but my understanding is as follows:
5 a day is your pieces of fruit and veg - I have read before this should be 2 fruit and 3 veg - a google search will tell you how much a portion size is. Also you should try and aim for 5 different colours of fruit and veg and this will cover all the nutritional values you'd need for example - green apple, black grapes, orange carrot, white cauliflower, red raddish.
for this plan I have read 150 minutes of exercise - combine cardio + strength
not sure how to answer your third point, but I hope these two answers start you off....
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