I'll try my best to answer your question: 1: The supervisor certificate of Communications Department is applicable to traffic projects such as expressways and national (provincial) roads, and the supervisor certificate of Construction Department is applicable to housing construction projects; 2. In terms of traffic engineering, if you have the competent certificate of the Communications Department, you can still be a supervisor across provinces and cities; In housing construction projects, the certification of the construction department has regional restrictions (the Ministry of Construction has no regional restrictions); This question is basically the same as that in 2. Being a supervisor is no problem. If you are a professional supervision engineer, you must obtain the certificate of supervision engineer from the Ministry of Communications. 5. Ministry of Communications: there are two kinds of professional supervision engineers and supervision engineers, and the supervision engineer can be engaged in the post of director at most; Ministry of Construction: There is only one kind of supervision engineer, and the certificates obtained by the following construction departments vary from place to place. You can ask them for a certificate from the Ministry of Construction. 6. As long as you are engaged in a project on the spot, you have to follow the project everywhere, and it is difficult to settle down. You should also carefully consider this point and be mentally prepared. This kind of work will bring a lot of inconvenience to your future family and children! Your supplementary question: You mean the head of the Ministry of Communications (training certificate). Generally, this is a supervision training course organized by various supervision units in conjunction with local traffic quality inspection stations and universities designated by the Ministry of Communications (such as Southeast University and Changsha Railway Institute). Only after passing the exam can you obtain the supervisor certificate (training certificate). If you want to take the exam yourself, you can consult the local traffic quality inspection station. Finally, I wish you can find one.