The human ear can clearly distinguish the sound, indicating that your computer has been used for a long time (maybe it has been used intensively for a while or the environment is not very good), and the fan needs lubrication. If possible, it is best to replace the blades of the cooling fan or even the whole cooling fan.
For the time being, you can put something with a skeleton under the notebook computer to let it dissipate heat better. I usually encounter such a situation. Putting four chopsticks under my notebook works well.
The above is my advice to you. The space at the bottom of the notebook can be temporarily expanded to facilitate heat dissipation. The fundamental solution is to lubricate the cooling fan or even replace the whole radiator.
I hope my answer can help you.