Can iOS 14 do split screen?

Unlike iPadOS (variant of iOS, renamed to reflect features specific to iPad, such as the ability to view multiple running apps at once), iOS has no ability to view two or more running apps in a split screen mode.

How do I enable split screen on my iPhone?

To activate split-screen, rotate your iPhone so it’s in the landscape orientation. When you’re using an app that supports this feature, the screen splits automatically. In split-screen mode, the screen has two panes. The left pane is for navigation, whereas the right pane shows the content selected in the left pane.