It would be really helpful already if the typescript typings had some information about what to provide where.
Trying
await strapi.entityService.findOne(
"plugin::users-permissions.user",
{
populate: "*",
},
ctx.params.id
);
and getting Undefined attribute level operator populate. The docs show only how to use populate for findMany: Entity Service API - Populating - Strapi Developer Docs
EDIT: It was the other way round:
let affectedRecordData = await strapi.entityService.findOne(
"plugin::users-permissions.user",
ctx.params.id,
{
populate: "*",
}
);