How can I set to allow all the people to access mysql databases??I mean like how to set wildcard so that anyone can access mysql databases.
By reading your comments, you want to access from another computer. This can be done the following way:
# bind-address 127.0.0.1
sudo /etc/init.d/mysql restart
Now you can add a new user (for example with phpmyadmin) an restrict the connection to the ip of the other computer.
You can add a user without IP-Restriction but this is highly insecure!