If you published the complete idea then it is now public domain. The law changed a few years ago where it first to file and not who had the idea first. The process is to file either a full patent or a provisional patent first. If you go the provisional direction you have one year to file for the full patent. My understanding is that after the one year the provisional is published and becomes public domain and is no longer patentable. There are three different types of patents. Design, Utility, and Agricultural. Design patents are where it is an original idea and there isn't anything like it. Utility patent is where lets say you had a jet fuel patent and I found it treated Covid 19. I could use your patent for own patent as an utility design and not infringe on your patent for the jet fuel. The first 5 patents you file are considered as a micro entity and the cost is far less then a regular filing. If you intend to file I would recommend signing up and getting an electronic filing number issued to you. This number is issued free of charge and allows the application to be filed with a lot less headache. Where people run into problems is trying to do the patent search yourself and not knowing some of the inside tricks. The USPTO office has some very good video to explain how to search without getting 50,000 returns. Before filing a patent you should always to your market research for the item to estimate the amount that can be sold. If you want 10 million dollars and you are only going to sell 10 then the price needs to be 1 million each. Are they going to sell at this price? If you want 10 million and you are going to sell 10 million then you only have to charge a dollar. Using these numbers would also provide information if choose to go the royalty direction. There is a lot of debate regarding whether is better to be the first to dominate the market or go for patent protection.