Country tag for Belgium is:
BEL
If you want play for Belgium HOI4 you could use tag command:
tag BEL
To annex Belgium in HOI4 you could use annex command:
annex BEL
To delete all Belgium units you could use deleteallunits command:
deleteallunits BEL
To add interests on Belgium you could use add_interest command:
add_interest BEL
To remove interests on Belgium you could use remove_interest command:
remove_interest BEL
To start occupation on Belgium you could use occupationpaint command:
occupationpaint BEL
More country tags for HOI4 or more cheats for Hearts of Iron IV