They ripen from the bottom and up. In your image, the yellow one at the lower right is already ripe. You can pick that one out and allow to fully ripen in your table in a day or 2 more. The ones near the top are still growing.

The green ones can be cooked like a vegetable.
We usually make a chicken soup with it. We call it "Tinola" or the full name is "tinolang manok". Tinola is the way it is cooked and manok means chicken.
https://en.wikipedia.org/wiki/Tinola

Sometime we would cover the growing fruits with a sack to protect it from critters, mostly birds.

Be careful of the sap of the plant, even the ones that may ooze out of the green fruit. It can irritate the skin and peel off the skin. Long exposure can cause wounds to appear several days later. No danger with fully ripe fruits as they do not have this sap.

For this reason, there are papaya products that is marketed as herbal skin whitener/rejuvenator.
*all images grabbed from the net.
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