Is it okay if I don't get a root canal?

I went to the dentist because I had a cavity, and they said I probably wouldn't need a separate root canal treatment.

I decided not to get a root canal, but to have an impression of my tooth taken, I’m scheduled to visit again next week.

I'm just curious, would it be okay to just fill it without doing a root canal?

I was curious if there was some kind of standard.

And sometimes a crown or resin is used, probably depending on the progression of the tooth decay.

So, the diagnosis would be different, right?

I'm so exhausted from getting dental treatment these days.