LSVD regression - how many dummies

hey, I'm back and making progress :)

I want to run a LSDV regression on my panel data. How many dummies do I have to include? All of them for years and units (countries)?

I read that results should be the same as with FE, but if I include all dummies, they are not (also if I exclude one time and one country dummy).

Thx for help!