How to add a target _blank on a WordPress menu item custom links

In WordPress custom links their is already build in choice check box ‘Open link in a new tab’, but by default it is hidden you can enable that from the screen options as in the below images

If you enable that options from the screen options tab automatically a check box will come as ‘Open link in a new tab’ like below image, check that check box and save now onward your new link always open in a new tab