From your 'My Hub' page (please see below)
If you go to the 'Menu' icon in the top right...
then select 'Nutrition' from the options
You will see a list of any nutrition plans you have created previously
If you then click on 'Create Nutrition Plan' at the bottom of your page
and enter the plan name
You can manually add your clients 'Macronutrients' and also any food items to each meal of the day by clicking 'Add Food/Drink Item'
Then simply search for any food/drink items as well as set the portion sizes for each
And click 'Add to Meal'
Once you've added all food items just hit 'Save Plan'.