Usually you can update Rocket.Chat pretty easily. In case of manual installations you can just replace the old version with the newer one. If you’re on Docker or similar deployment methods, just pull the new image (Docker), refresh the snap (Snap installtion) or just use whatever means your deployment method allows for.
Please also have a look at the installation documentation for your method of deployment to check for paragraphs that refer to the process of updating Rocket.Chat.
There might be some major changes when we introduce big new features or modifications, you can always take a look on the releases page to see what has been changed, broken or added to Rocket.Chat.
You can see older major changes here: