I doidn't realized what it was like to lose smell or smelltaste before.

When I ate todayhis morning, l realized l don't have smell or smell,taste. I ate the beef,it felt like a cow big,and when I ate Shachima it felt like sponge.It's very strange!

Don't have smell and taste

I have no sense of smell or taste / I don't have a sense of smell or taste

I don't realized what it was like to lose smell or smell before.

I hadn't realized what it was like to lose one's ability to smell.

I used to remember that state.

I remember how nice it was to be able to smell things.

When I ate today morning,l realized l don't have smell or smell,I ate the beef,it felt like a cow big,and when I ate Shachima felt like sponge.It's very strange!

When I had breakfast today, I realized I can no longer smell anything. When I ate the beef, it felt like I was eating an entire cow, and when I ate shachima, it had the texture of a sponge. It was very strange!

I can't smell the aroma of apples.

I can't even smell apples.

And I start to feel dizzy by bus and cars because the unpleasant smell of cars.

I used to feel dizzy because of how unpleasant cars smelled.

Although it's good in this way, I still hope that I can recover as soon as possible.

Although there are benefits to this, I hope I go back to being able to smell. Sooner rather than later.

I don'tnever realized what it was like to lose smellmy sense of taste or smell before.

Don't is for ongoing things including right now, never is more appropriate when looking back like this.

I used to remember that state.

Not sure what the intended meaning is here

When I ate todayhis morning, l realized l don't have smell or smell,couldn't taste or smell anything, I ate the beef, it felt like a cow big, (?), and when I ate Shachima feltit tasted like sponge. It' was very strange!

Spaces are expected after punctuation

You don't combine don't and couldn't, couldn't on its own is correct.

It sounds more natural not to omit the object for these verbs.

Not sure what a "cow big" is meant to be.

Feel can sometimes be used for the sensation of items in your mouth, but it's more about texture than flavour. When talking about losing a sense of taste, it's usually about flavour so it's better to use taste than feel here.

And I start to feel dizzy byaround bus and cars because of the unpleasant smell of cars.

By and around are sometimes synonyms, but it sounds more natural here to use around.

You can use "because <action>" or "because of <thing>". In this case, the "unpleasant smell of cars" is a thing, so we use "because of'

Although it's good(ok/tolerable) in this way, I still hope that I can recover as soon as possible.

Good is too positive an adjective for the contrast you're drawing here.