Introducing the portal gun add-on.
This add-on adds an item in your world called a portal gun.
You can make the portal gun b
y using This Recipe:

Here is a demo video:
The new version Portal Gun v5 update:
- Now only works for a single player
- Can now carry specific blocks (dirt,grass,diorite,granite,andesite,redstone,obsidian,netherrack)
By sneaking and hitting a block then quickly unsneak
To place just sneak
- Added a 3d model
- Improved portal death animation
The new version Portal Gun v7 update:
- Added rick and morty portal gun along with rick and morty portals
- Added Glados portal gun along with the original portal
- Added the ability to make black holes.
- Portals no longer despawn
- portal no longer take damage
Instructional video: