My leaves on zucchini are huge, but no fruit is making.
My Leaves on Zucchini Are Huge
Certified GKH Gardening Expert
If it is a problem of not getting any flowers, I would recommend adding some phosphorus to the soil. This article will help with that: https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/phosphorus-plant-growth.htm
If it is a problem of flowers not producing fruit, you probably have a pollinator problem and you may need to hand pollinate. These articles will help with that: https://www.gardeningknowhow.com/edible/vegetables/squash/pollinate-squash-by-hand.htm