Question

How long did it take for the sun to form?

Answer 1

I don't think there is an accurate answer.

Explanation:

We observe that it happens, but too slowly to measure on human timescales. Many millions, but probably not billions of years would be a sensible estimate.

Answer 2

It took about 50 million years for the Sun to form.

Explanation:

Stars form out of disks of mainly Hydrogen and helium which start to collapse under gravity.

Once the protostar forms it takes millions of years for the core temperature and pressure to increase to the point where Hydrogen fusion can start.

The process of getting the temperature and pressure to the point where Hydrogen fusion takes about 50 million years for stars like our Sun.