Altium Designer multi sheet design quad op amp
I believe what you want is a multiple part symbol, they allow you to split one package or part into subparts. There is a great tutorial at altium that describes how to do this

After you create a part that has multiple parts, you can place the parts anywhere in your design and altium will recognize the part as the same part as long as you keep the designatior the same. The designator will also have have the subpart letter in the part name. For example: a part with U3 with an A and B subpart has designators U3A and U3B 


Source: https://resources.altium.com/pcb-design-blog/in-your-altium-library-multiple-part-symbols-ease-your-design-time