Service provider return undefined http request

I have this issue with http request to my server and I got returning as undefined in my app.component.ts file.

My provider function looks like this:

async getPostBySlug(slug){
  let postBySlug=await this.get("posts?slug="+slug)
  await postBySlug.subscribe((post:any)=>{

and then my app.component.ts function is starting on initializeApp() and looks like this:

private async onPushOpened(data) {
    let url = data.notification.payload.launchURL
    let slug = url.split('/')[4]
    //this.nav.push(DetailPage, {post: this.api.postBySlug})

Where I’m mistaken all of this?
Why I can’t get response value on my app.component?

If you don’t get any better answers, I would try rewriting all this pretending that async and await don’t exist. That should make it more clear what is going on.

I have a response in my provider and works well, but I can not use that response in my app.component. Neither as return or by using
It shows Object only in my provider. I’m stuck in getting it in my app.component, is there any other way to do that?
I put async later because I was thinking that maybe It needs to wait for data. But also without async it doesnt work…

If you get in the habit of always providing real types for every variable, parameter, and function return (never any), and avoid async/await until you are rock-solid confident in what they are actually doing under the covers, your build tools and IDE will be able to provide you ongoing detailed guidance about what is happening here.

You are mashing up reactive and imperative programming styles in an untenable way.

Well, you have right somehow. I just reorganize my code and my personal view of everything and I have finally made this work. Thanks anyways for your help