Download and Install Android Studio
Goto Android Studio download page
Click download Android Studio for Windows
Accept the license agreement and click download.
Define JAVA_HOME Variable
After the installation you will probably get the following error if you are not define the Java Environment Variable.
Open Computer > Select System Properties
Select Advanced system settings > Click Environment Variables
Click new in System variables
Type variable name as JAVA_HOME
variable value as the path were the jdk installed
The default location is C:Program FilesJavajdk1.8.0_25
Click OK and open Android Studio
If your SDK manager is not accessible run Android Studio in Administrator mode, Right Click Android Studio > Select Run as administrator