Well, for the moment there are no banks that accept bitcoin, because bitcoin is not legalized officially, so, although some countries do not prohibit the use bitcoin, but it will not come to the bank, except bitcoin to form its own bank. well, but one day there may be banks that accept bitcoin.

It is basically the same bullshit that government agencies often reply to requests sent by citizens (though courts are beyond competition in this regard). You ask them precise questions but get as a reply something which is totally irrelevant to your inquiry. They obviously fail to understand that by doing this they lose any respect that people might feel toward them. In this case, they are warning about bitcoin being used for illegal activities and suggest that you should stop using it as though you are already engaged in some criminal business involving Bitcoin...

Why don't they suggest to stop using their own money as well since it is also used for illegal activities?

Well thats really the first impressions of most people since the rise of deep web and they are getting curious of deepweb and also it involves bitcoin in it ! So at first if they hear the bitcoin they think it is only use in illegal activities but not! Money too our own fiat but some of it is not using it in bad.

I think compare the last year we will experience more people are trusting bitcoin right now.. for those new about bitcoin or if they didn't know about bitcoin they are always think that bitcoin is scam or use for illegal activities this is what i experience before and i think this year we will see more people can trust bitcoin since bitcoin is already adopted and more company and merchant right now are accepting bitcoin as payment unlike before.

There are no banks who accept bitcoin, but with the majority of banks you can withdraw money to an exchange and buy bitcoin.
I use kraken and when i want to buy bitcoins i just iniatiate a SEPA transfer and voila i can buy bitcoin.

i believe there is in the world , but in fact in my country i not see yet ..

You are right there is no any bank right now in the world which is using bitcoin. as there is no any state which have allowed their institutes to start accepting bitcoin for their uses. Maybe in the future we find to see some of them.

but i think no one bank accept bitcoin in anywhere because bitcoin is a just crypto currency we can just use it as digitally  and bank just accepting fiat regular currency and if any government accept bitcoin then i hope that bitcoin will become in physical shape and it will be acceptable in bank.