white lining and spots on zucchini plant
the yellowing of the leaves is probably caused by downy mildew: turn over the leaves and look for a "fuzzy" mold. It is very hard to control, especially with a home remedy. A mixture of 1 table spoon of baking soda, a teaspoon of horticultural oil mixed into a gallon of water might slow down the spread of the disease (it is not a cure).
Make sure to remove disease leaves and throw them in the trash.
Anything with a chewing mouth part could have caused the holes in the leaves: my guess is cucumber beetles.I do not know of a home remedy and I am not sure what kind of other remedy to suggest since I see you are outside of the US.
Hope this helps a bit.