what is the difference between package.box and ubuntu.box above?

ubuntu.box does not include your later installed lnmp environment
package.box contains your later installed lnmp environment

I don't know if you have installed a computer system.
ubuntu.box is the equivalent of a system image file. vagrant box add ubuntu E:ubuntu.box can be deleted after that. Lnmp environments installed after
are not stored in ubuntu.box.
vagrant package the packaged package.box is equivalent to making a backup image of your current system, and this box will have the lnmp environment you installed later

one is your build base package
the other is your build package-> you must be sharing this box

both are packages, of course, others can continue to build based on your build package. Here is a concept, but one is your environment package