which site?

how I can find fully founded courses for master of financial Mathematics?

Use google and search for "fully funded courses for master of financial Mathematics" in the UK, US, and other countries as well. Also consider mathematics/statistics degree programs that have some financial math courses available. They might be more likely to have funding. Also there are specific funding scholarship programs for different groups. For example, Cambridge has international scholarships, Oxford has funding from Jane Street, Manchester and Martingale, and the British Council offers Women In STEM scholarships. Some universities offer general master's scholarships. There are also a few programs in the US that offer fully funded masters level scholarships. Spend some time and do your research carefully.