So I am looking for a university where I can run a master's degree in bitcoin since I already have an undergraduate degree, I was thinking El Salvador will be the best country to expect such a university because El Salvador is 100% bitcoin-friendly please any suggestions?
I don't think you will find any master's degree in BTC, even though you might see no course directly pertaining to BTC. Because institutions have to register them with the respective educational system of their country and to approve the course, it must be according to the laws and regulations of that country (which means countries that have banned crypto usage, are unlikely to teach a registered course in any university about BTC).
But you will find courses to learn BTC by different names, like Blockchain. because blockchain changes the purposes as it has its own benefits, even for governments. Now, to your question about which university to attend. I think first you should share a little bit of information about your geographical and financial status. like how much you could afford and whether you could go to another country to learn these courses. or you are querying about
"online courses".
Here is an article covering most of the registered courses about BTC/Blockchain to learn in universities. (In the list I would prefer you to not select
Massachusetts Institute of Technology (USA) because that state has senators that hate BTC and well at least show their hostility about it,
you can read the topic about it has already been discussed).
If you are looking for online degrees in this field, then this article might help you,
7 Universities Offering Online... El Salvador's adoption of BTC as a legal tender has been of less benefit to them till now, Who knows the future, but at the current state, they are facing difficulties and their citizens are too.