As far as we not today, universe is at least 46 billion light years in radius.
But its estimated age is about 13.6 billion years.
So actually we don’t know how big the universe is and it may not be possible to know. If the universe is a closed space, we can estimate its size (which will be trillions light years in diameter). As of today it is not clear if it is flat or curved. Some new articles show that the curved hypothesis cannot be discarded.
Since we have predictions on how the early galaxies should look like, the James Webb telescope may confirm or not those predictions. Even Hubble telescope allows us to verify predictions about the universe age and size.
Those two articles above explain quite well what we know about the size and the age of the universe. If you are really interested, read them.
