What preparations are needed for children who require special support at Seoul International School?

Hello, we are a young family planning to move to Seoul soon. Our son is 5 years old and needs additional support in his learning. He has a bright and happy personality, but he struggles to make friends and participate in class due to social anxiety and a speech disorder. Currently, we are receiving speech therapy and occupational therapy in our home country. Our child is set to enter the first grade at a well-known British international school in Seoul. We would like to know how international schools in Seoul handle children who need such special support. We are curious about what preparations we should make or if there are any changes we should be aware of. We would appreciate any help to ensure that he can adapt well to the new environment in Seoul.