Hi,
That's a good question. Let's get you some details for the water filter.
You'll need a water line kit, a water filter installation kit, and a filter cartridge (Sold separately). Here are the links to guide you on how to connect all of them properly.
Connect and install the water line to your Samsung refrigerator
https://www.samsung.com/us/support/answer/ANS00063062/
Connect the water line (optional) on pages 19 - 23
https://downloadcenter.samsung.com/content/UM/202207/20220713145434133/TMF_RT6500M_DA68-03570A-15_EN_MES_CFR.pdf
Should you need more assistance, please feel free to get back to us via the following options:
1. Facebook Messenger: http://m.me/Samsungsupport
2. Twitter: https://twitter.com/messages/compose?recipient_id=18768513
3. Samsung Community: https://us.community.Samsung.com/t5/Samsung-Community/ct-p/us
When you message us, please provide us with this reference number (1145085724) to help our team pull up your information.
Have a great day.
^Charles