The upraising should not have taken place until the people were fit and ready. So many civilians were badly affected due to this hastiness.
The régime is a kafir regime and it is permissible to overthrow it but not until the people are ready.
This is too late now and people must fight till the death. However, it is not advisable for foreigners to join the army as there isn’t a unified flag and foreign fighters would only hinder and delay the Syrian trained people.
May Allah grant them victory and liberate the Muslim lands from such Kufr.