@jess505 If you go to https://downloads.vivaldi.com/ you can select and download the latest version for your platform and stream. If you're on Windows 32-bit, Windows 64-bit, Linux or Mac, if you're on the Stable stream or the Snapshot stream, you can get the appropriate download for your machine and the version you are currently running.
That link is "official," but it is for Windows 64-bit, one version ago, not necessarily for your situation.
NOW - to simplify matters, you can go to Menu/Help/Check for updates in your own copy of the browser and it will automatically detect any available update for your version. You can accept the offer to download and install that update, and it will do it for you, no matter how your copy is installed - user only, all users, or standalone. Your installation knows what version it is and how it is installed, and will only seek and accept a correct update for itself.
If you go to a destination on the web and download an installer for a different version, you can actually wind up changing your installation to a different KIND of Vivaldi (32-bit instead of 64-bit, stable instead of snapshot, snapshot instead of stable, or whatever.) The automatic update will only look for what you are already running.