Intro component with sign up form validation using TypeScript

Hi together, I have some questions marked as comments in my source code:

Considering HTML:

1. HTML5 Semantic and <label> tag

Considering CSS:

1. Is it better to use CSS grid or CSS flex for layout?

Considering TypeScript:

1. Name conventions
2. structure and readability of the code

In general:

1. Why is my form submitted if I typed in everything correctly expect the password and submit the form?

Thanks!