Travel Restrictions COVID

Something that is rarely covered and hard to find - restrictions based on location, not a passport. I have not been in the US since 2017 but carry a US passport. Pre COVID I spent the majority of my time in Georgia, Turkey and Ukraine and have been in Albania for a EU project since March 3. Does anyone know how travel restrictions are handled at borders. Although I have a US passport, I am not coming from there and don’t want to be subject to some rule based on citizenship.