First of all: I would not buy anything from Israel.

Second: GMOs are basically the same as selectively bred organisms, just with a different process of arriving at the same goal. Selective breeding is a form of genetic modification but GMOs usually refers to gene editing being involved.

• Are patented seeds of sweet seedless peppers from breedx.com GMO? They say no on their website.
• is it legal to use biological waste after consuming [GMO]?
  Yes
• [are GMOs healthy]?
  GMOs are not unhealthy per se, it depends on the modification. The main problem is that many GMOs are designed to be resistant to certain pesticides that are then overused. (not a problem if you buy seeds and raise them yourself without pesticides)
• how patented food/seeds works?
  A company creates a new strain of a plant trough selective breeding or gene editing and applies for a patent.
• what are implications for society? The results of modern agriculture are typically correlated with GMOs are:
  Reduced biodiversity, insects dying, pesticide overuse. Patented seeds mean farmers can't use part of their own harvest as seed stock and have to buy new seed from the company each season, and farmers on neighboring fields are at risk of being sued if patented seed fly over to their field.

The same way breeding grains for higher yield was vital for agriculture since the beginning, gene editing enables resistance to some consequences of climate change and vitamins in normally vitamin poor food. These advancements will be vital in feeding humanity in the future.

In summary GMOs can be used for good or bad, but patents on them are just evil.