I deleted safari on my Mac computer, how do I get it back on?

Reinstall the OS.

1. Start up from macOS Recovery

To start up from macOS Recovery, turn on your Mac and immediately press and hold one of the following combinations on your keyboard. Command-R is generally recommended, especially if you never installed macOS Sierra 10.12.4 or later… https://support.apple.com/en-us/HT204904#notupdated

Command (⌘)-R

Install the latest macOS that was installed on your Mac.

Option-⌘-R

Upgrade to the latest macOS compatible with your Mac.

Shift-Option-⌘-R

Install the macOS that came with your Mac, or the closest version still available.

Did you look for it in Applications? How about Launchpad? Did you try Spotlight?

It is not normally possible to delete Safari, but you may have dragged it out of the Dock. When you find it, drag it back into the Dock.

Any luck yet?