Hi Jackie,
As Niki said, you need to apply through the Primary Assessment Gateway.
Gov.uk have a really helpful document about access arrangements and evidence needed- we had the LA come in for monitoring once and they did ask to see it.
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1109963/2023_key_stage_2_access_arrangements_guidance.pdf