The member states are the 28 building blocks of the EU, and meet in the Council, where one Minister from each member state sits down to find a compromise on whatever is on the table.
A few times a year, the Council meets as “The European Council” when the heads of government meet to set the overall political direction of the EU. Usually though, the Council meetings are about technical negotiations over technical legislation, with the Council being co-responsible with the Parliament for amending and negotiating legislation proposed by the Commission.
The Council and the Parliament, acting together, agree laws, but even then the laws do not actually enter into domestic law. This only happens when they are approved by either the Scottish Parliament or the Westminster Parliament. Both have the flexibility to implement the laws in the way best suited to them. This flexibility is threatened by Brexit as the final say over how Scotland implements policy in these areas will be held by Westminster.