Question about orthodontics for a 20-year-old male.

My oldest child, who turned 20 this year, had relatively straight teeth when they were young, but as they got older, a few days ago while talking and looking at their face, I saw their teeth and was really shocked~ㅠ

Both the groom and I have fairly even teeth.. (My family is okay, but in-laws, including my sister-in-law and mother-in-law, also have uneven teeth)

Is it true that having unattractive teeth is also inherited?

It's so messy that I keep thinking about it afterward. The problem is the orthodontic cost and appearance... It's a time when I want to dress up and meet many people. If I start now, I wonder how many years it usually takes and roughly how much it costs.

Are there different types of orthodontic treatments, just like there are various types of dental implants and resin?

Which is more effective: correcting it during childhood or as an adult?