Hello,
I am not sure if You realised it yet but this is NOT a GNS3 support forum.
Just for Your reference, You have to jump though extra hoops to get vMX working in GNS3
https://docs.gns3.com/144QvvLxBT69_fv-pPHf4etc5xjdItiA_a8s8gVmSTDk/index.html
https://www.gns3.com/discussions/how-to-simulate-juniper-routers
Specifically, You have to map & configure ge-* interfaces for vMX in GNS3, not em* as it used to be in older JUNOS images - this is the reason for Your grief.
But why not use vMX free trial with proper instructions?
Download 60-day vMX eval https://www.juniper.net/us/en/dm/free-vmx-trial/
vMX installation instructions
HTH
Thx
Alex