How to install gtk+2.0

When I enter the command

sudo apt-get install gtk+2.0

I get Output is like this:

Reading state information... Done
Note, selecting 'gir1.2-spice-client-gtk-2.0' for regex 'gtk+-2.0'
Note, selecting 'gir1.2-gtk-2.0' for regex 'gtk+-2.0'
Note, selecting 'libspice-client-gtk-2.0-dev' for regex 'gtk+-2.0'
Note, selecting 'libspice-client-gtk-2.0-1' for regex 'gtk+-2.0'
Note, selecting 'gir1.0-gtk-2.0' for regex 'gtk+-2.0'
gir1.2-gtk-2.0 is already the newest version.
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libspice-client-gtk-2.0-dev : Depends: libgtk2.0-dev (>= 2.18.0) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

I am new to Ubuntu what I have to do?

The right command is:

sudo apt-get install gtk2.0

First you need gtk2 and the command for that is

sudo apt-get install gtk2.0

chances are that its already installed.

Then you need the development package libgtk2.0-dev and this can be installed by the command:

sudo apt-get install build-essential libgtk2.0-dev