For travel to most countries, submitting the PDF declaring that you are healthy has become a mandatory step. Being an essential requirement, it should be made easier for travellers to access these forms. Nowadays it is an odyssey. Sometimes it is simply impossible to find them by searching on Google, or worse, when you do find them, the form is not in a language you can understand. It also often happens that the websites don't work or seem very unreliable; in short, it's chaos.
That's why MOGU recommends using this tool: you only have to enter the destination you are travelling to, your nationality, fill in a series of steps in 5 minutes and they send you the PDF to your email. It costs about 20€ to do it with them but it's worth it because not only do you save time but you travel with the guarantee of having a secure document.
In case you prefer the traditional method, here are the websites of the PDFs by country: