Don’t worry or panic.

Looks like the root resorbed naturally. So the remains you see could be very tiny and /or the permanent tooth is erupting. Either way in most cases it will take care of itself. So don't worry.

You should wait for sometime it shouldn't cause any problem, ideally the remaining part should be going under resorption. As now the covid case's are high wait for some more time and then visit your regular dentist and get an x-ray done,to check how much is remaining.

Even if it's a retained part of the fallen tooth with further pressure from underlying permanent tooth it will get mobile and may come off on its own in a month or two. Nothing to worry.

Looks natural shedding aided with hard bite. Don’t worry. What you see beneath is probably permanent tooth coming. 5 is the age. But to confirm all this with a radiograph and check up.

The regular age for milk tooth to fall out is six years If you’re tooth gets broken and little bit of root remains in the gum and Bone it is not a problem. You have to wait for the permanent tooth to grow out. The roots resorb . If you see the permanent tooth is not able to grow into the proper space and the milk tooth the root is obstructing then you have to go to the dentist and get it extracted.

It could be the permanent tooth erupting. You can visit a nearby dentist and get an X-ray done to examine the remaining part of the tooth but Nothing to worry it will come out on its own.