Q.cucumbers that don’t turn dark green
My cucumbers grow to about 8 inches or more but don’t turn the green you see in stores. They remain very light in color or remain sort of a very light yellow. Am I doing something wrong? They are planted in a very sunny spot.

Do you know the characteristics of the variety you are growing? Check the back of the seed packet if you started them from seed. It will have estimated harvest size and the color characteristics listed on it.
Did the cucumbers start out green, then lighten as the go larger?
You may be waiting to long to harvest your cucumbers.
If the cucumbers are just growing and are yellow from the start, this is most likely a soil nutrient issue.
A soil test could identify the issue, but you need some help quickly.
I like to use Epsom Salt for feeding my vegetable plants. I would give this a try.
I like to spread about 1/8 cup of Epsom Salt around the base of the plant once a week. Water it in.
Here are some links for you.
https://www.gardeningknowhow.com/edible/vegetables/cucumber/when-to-pick-a-cucumber-how-to-prevent-yellow-cucumbers.htm
https://www.gardeningknowhow.com/edible/vegetables/cucumber/how-to-harvest-cucumbers.htm
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/epsom-salt-gardening.htm