Thanks Dominic23, but it does not work.
I should have said that I tried this before, as it would be the standard way of getting rid of problems, but in this case, the site "viperdns.com" takes precedent on most of my intents to enter another URL. I also performed a "Software Update" and restarted the device several times. I do not use another browser and this is happening only in Safari. What happens is that if I try typing a new address or a question to google (default search engine) this website takes over and blocks any intent for the original comand to load. Some websites work, directly from "Favourites" and by typing the address, but most of them do not work and most of the times I end up confronted with this Viper company trying to sell me their services but before I should change or as they say, update "Primary DNS" and "Secondary DNS". The address that keeps repeating itself is: "https://www.viperdns.com/error-olddns.html".
It is only happening in my iPad, but not yet so in my iPad Mini, nor in my iPhone or in my MacBook Pro.