What you have above is an object, not an array.

To make an array use [ & ] to surround your objects.

userTestStatus = [
  { "id": 0, "name": "Available" },
  { "id": 1, "name": "Ready" },
  { "id": 2, "name": "Started" }
];

Aside from that TypeScript is a superset of JavaScript so whatever is valid JavaScript will be valid TypeScript so no other changes are needed.

Feedback clarification from OP... in need of a definition for the model posted

You can use the types defined here to represent your object model:

type MyType = {
    id: number;
    name: string;
}

type MyGroupType = {
    [key:string]: MyType;
}

var obj: MyGroupType = {
    "0": { "id": 0, "name": "Available" },
    "1": { "id": 1, "name": "Ready" },
    "2": { "id": 2, "name": "Started" }
};
// or if you make it an array
var arr: MyType[] = [
    { "id": 0, "name": "Available" },
    { "id": 1, "name": "Ready" },
    { "id": 2, "name": "Started" }
];

You can extract it by pointing at an array member, so while you are using the below code to get the type of the array:

type A = typeof input;

You can use this to get the type of a single item:

type B = typeof input[0];

Starting with TypeScript 2.8 you can also do this with the infer keyword. This should only be used for more complicated cases (arrays nested in promises, etc), otherwise it is overly verbose.

type GetElementType<T extends any[]> = T extends (infer U)[] ? U : never;

For example:

// ElementType === string
type ElementType = string[] extends (infer U)[] ? U : never;

The infer keyword is very powerful and can extract any type out of larger type. For example if the type was a function that returns an array:

type FncType = () => [{ name: string }];

// Output === { name: string }
type Output = FncType extends () => (infer U)[] ? U : never;

You can also use the infer keyword in generic types:

type GetArrayReturnType<T> = T extends () => (infer U)[] ? U : never;

// Output === { name: string }
type Output = GetArrayReturnType<() => [{ name: string }]>;