How easy is it to grow flowers, vegetables, and fruits in the same greenhouse? Will the fact that I will be growing different types of plants (flowers, veggies, fruits) and within the catagories growing a variety of things (Example: flowers-orchids, sunflowers; veggies-carrots, cabbage; fruits-kiwies, stawberries) make it difficult to have all of my plants survive? This will all be done in a greenhouse. Also, will I have less trouble when it comes to pests growing plants in a greenhouse or will the trouble be the same as if I were growing these plants out doors?
All of the plants you mention can be grown in a greenhouse, although grape vines and kiwifruit vines can be a bit vigorous. Sunflowers are a bit tall and do not need a greenhouse, nor does cabbage, except to raise seedlings of planting out.
Anything that can be grown outdoors should be grown outside the greenhouse as they waste limited greenhouse space the might be given to plants that need high summer temperatures.
Pests are more troublesome in a greenhouse: for 2 reasons. 1. the higher termperature favours insect development. 2. there are few, if any natural predators and parasites.
Therefore, it is necessary to keep a close watch for pests and control them if necessary.
 More information on greenhouse growing at: https://gardenie.wpengine.com/gerrycategory/protective-structures/?id=5470