[Question] About teeth whitening

My teeth are somewhat yellow, so I was thinking about whitening them and looked into teeth whitening a little...

Having superficial knowledge makes me even more hesitant about teeth whitening...ㅠㅠ

My teeth are uneven and my tooth color is quite yellow, so I worry a lot about social interactions...
I recently got and am using toothpaste that is said to be good for teeth whitening...^^

What you are curious about

1) Is it true that teeth whitening causes severe tooth sensitivity?

2) Does teeth whitening actually damage teeth?

Is it true that you should avoid eating colored foods (such as kimchi, coffee, etc.) for about a month after teeth whitening?

Is it correct that teeth whitening needs to be done regularly?

Have you ever had teeth whitening?

Please share your good opinions if you have knowledge about teeth whitening...^^