How can I call an async function synchronously?

I want to call an async function synchronously. I am doing this by calling without await. But the async function itself is making a call to another async API method using await . Will this convert my synchronous call to asynchronous?

const myCall = this.myclient.getAssessment(); < --- Is this still going to be synchronous or will it be converted to async?

Client:
const async getAssessment(): Promise<>{
    const callThirdAPI = await this.anotherClient.getValue()
}

I want to wait for this.myclient.getAssessment() to return the value so that I can use myCall later in the code.

I was thinking of calling it asyncly and using .then() to read the value and return it, but typescript is throwing an error saying I am not returning the specified value.

This is what I was thinking:

private myFunction(){
   const myCall = await this.myclient.getAssessment();

   myCall.then((response) => {
      return response
   });
}

But typescript complains that myFunction() is not returning a value.