Under My Foods, go to Recipes, Create New Recipe. Create the meal as if it were a recipe. Then when you want to repeat the meal, just look for it in My Foods.
I make a "recipe" that includes everything in a meal. Or several. I have one that's the cream and sugar in my morning coffee, the ingredient in my normal egg white omelette. Etc. Then I just click on the recipe in "my foods"
If you go to the meal from the previous day that you want to copy there are the 3 dots next to the meal if you click on that there is an option to copy to just pick the date.