In which way I shall get cactus and adenium seeds in my country for my home garden?

Google what seeds you have interest in, something like "Purchase cactus seeds", and something should come up that gives you that information.

You might be best advised to check the regulations on importing seeds with your Department of Agriculture. Some places allow free importation of seeds, but not living plants but other places such as Australia are extremely strict and require phytosanitary documentation for anything related to a plant. It seems to be different for each country.