I need to install the operating system for my samsung note 4

Googled Blu phone. Blu phone is an android device. Android is another name for google. Specifically android is googles operating system. If you were looking for another contact list you will have to download an app and set that up. But on this part you are on your own for now. I an an Android user and like it that way.
Hope this helps.

It means that you are using a smartphone that is not power by Google Android, You probably have a smartphone that it does run on Android, but since Android is open source, anybody can build an Android OS and install it in a compatible device.

You could try this site:
Install KitKat 4 4 2 XXU1ANFB on Galaxy Tab 10 5 SM T800
Install KitKat 4 4 2 XXU1ANFB on Galaxy Tab 10 5 SM T800

Unfortunately, at the moment, Whatsapp only supports the following phones: 1. Android 2. iPhone 3. Symbian(other nokia devices ) 4. Windows Phone Your phone is not on the list as far as I know and it is not android phone. In order to use whatsapp application, your phone needs to meet the requirement and that is android 2.3.5 for android softwares. If you really want to use whatsapp and you have a PC, you can use whatsapp on your PC/laptop using bluestacks. How to install bluestacks on PC ( see screenshots below for more details ) 1. Download bluestacks here : http://www.bluestacks.com/ 2. Install after downloading 3. Click 1 Mobile Market 4. On the search bar, type Whatsapp 5. Download and install.

One of the big selling points of Android devices was their Adobe Flash compatibility. Now that flash is being phased out of convention, you won't be able to download flash from the Play Market. That however doesn't mean that you can't get it.Here is briefed tutorial http://www.careace.net/2012/10/03/how-to-manually-install-flash-on-your-samsung-android-device/ for Manually install flash on your Samsung Android Device

You need to install a player for youtube. I will attach a link below. Make sure your android tablet supports this software. Some low end tablets will not play youtube.
Thanks for using FixYa

https://market.android.com/details?id=com.google.android.youtube&hl=en

Almost all smartphones including high end Android phones don't support flash but this may change in the future.

Operating system in D980 is Samsung's own. It's not open OS nor smartphone.