The Galaxy Tab S3 is the most powerful Android tablet for multitasking; you just need to take advantage of all it has to offer. It’s running Nougat, so split-screen is supported in almost all apps. Weirdly, the quickest way to open split-screen mode is off by default. Head into Settings > Advanced features > multi-window and turn on “Split-screen view action.” That lets you long-press the overview button to move an app to split-screen.
Samsung has also retained its custom Pop-up View, allowing you to also have apps run in a floating window. This doesn’t work with all apps, but it’s still useful. To open Pop-up View, drag down from the top left or right corner to set the window size. Both split-screen and Pop-up can be active at the same time for a remarkably desktop-like experience.