Are there coins (if created) a risk for bitcoin? Can compete bitcoin with these coins which will be supported by the most important Authorities of every country?
They'll be about as much of a threat as
Mintchip was. We already use digital currencies supported by the authorities of every country, it's called having a bank account. Whatever they end up creating will have literally no perceivable benefit to anyone beyond what we've already got today. No system with an unlimited monetary supply, central points of failure, and inherent shortcomings with fungibility and censorship (which is exactly what they'll come up with) will look like it's worth anything compared to Bitcoin. All they can do is create a pale and crippled imitation. There's no contest.
I completely agree with you. Let me add that banksters and governments are a bunch of greedy idiots. They will not stop. They will realize that their digital tokens give them much more possibility of control than paper money as we know it at the moment. When they realize this, they will go all in and they will make people complete slaves. If ever, people will realize at this moment that their governments are there only to rip the skin off of their backs.
MikeyB thank for your comments.
Before asking something to you I want to tell that I don't see the world such "black" as you.

Even I live in a country which is not to much developed. Our level of corruption here is very high and our politicians (according to me and with few exclusions) are probably the most irresponsible and corrupted people in the world. But I think again that there is good that our money are regulated by our Central Bank and the control of money exist, is managed and controlled by the Central Bank and with other Governmental Agencies. Otherwise all the "black" money will destroy everything here.
Anyhow, I wanted to know from you the answer of the main aim of this thread. What it would be the future of bitcoin if the countries of the main post (and other ones which might follow those in the future) will adopt as a national currency a digital based coin currency and will ban bitcoin to protect their new digital based coin money?
You need to ask Cyprus people is it good when you government takes care of your money. More than half of their money gone. Also you might ask Greek people (the hard working Greek people that have worked over 40 years and woke up one day with half of their savings gone or heavily controlled by their government and unavailable to access to them).
Now your second question. I don't think these governments will ever ban Bitcoin even if they develop their own centralized tokens. Why? This is not how it's done in the real world. If you ban Bitcoin, then Bitcoin will become forbidden fruit and people will want it even more in my opinion. This will just give a sign to the world that we are doing the right thing. What they will do in my opinion is that they will try and beat us with their centralized solutions. And they will have an advantage in my opinion until their whole debt system doesn't fall apart, which is inevitable!