Many "real-life intersections" are difficult to realize in Cities: Skylines, as the asset editor often does not give the size for such projects. Especially when it comes to extended freeway entrances and exits, you can reach the limits of the editor.
The mod Fine Road Anarchy makes it possible to place roads with no restrictions on steepness, shape and distance to other objects. As soon as you have subscribed to the mod, check in the menu whether it is also activated.
To build beyond the limits of the asset editor, the editor grid must be deactivated. To do this, click on "Toggle editor grid".
Now that the grid is deactivated, your building space is unlimited. The camera can also be moved freely and no longer stops at the edge of the editor.
The intersection in this post does actually exist, it is located in the US state of Florida. You can download it in the Steam Workshop: