I am kind of new to SQL server database. I am using sql server 2014 Can anyone help me to install SSIS DB. Is it mandatory to install to SSISDB
The documentation in BOL shows the process to create the SSISDB (SSIS catalog). You will have to have SSIS already installed on the given SQL Server instance before trying to create it.
The only reason this catalog would be required is if you are using the project-deployment model for your SSIS environment. If you are using the file system or SQL Server store/msdb then you do not have to create it.