Q.Thinning Watermelons That Are Producing
I have watermelon plants in 5 gallon buckets and they are doing well. One has a melon about the size of a baseball the other I’ve planted with peas, is producing 6-7 marble size fruit. They both, one is on full sun the other is partial, want to vine and crawl out of the bucket. 1.) how to train vines up a Shepard’s hook and 2.) how and when to thin (detach little melons)

Certified GKH Gardening Expert
Generally, anywhere from 2-4 melons can be supported on one plant. Here are some articles that will help you to thin and grow them on trellis:
https://www.gardeningknowhow.com/edible/fruits/watermelon/removing-melon-fruit.htm
https://www.gardeningknowhow.com/edible/fruits/watermelon/watermelon-vine-support.htm