Initial help with official “create a block” tutorial

Glad that you managed to fix the 3rd issue (block validation failed), and as for the first and second issues, you can fix them by using useBlockProps in your block’s edit callback:

// In src/index.js

import { TextControl } from '@wordpress/components';
import { useBlockProps } from '@wordpress/block-editor';

export default function Edit( { attributes, className, setAttributes } ) {
    const blockProps = useBlockProps();
    return (
        <div { ...blockProps }>
            ... your code.
        </div>
    );
}

See Developer Documentation → Block API Reference → Edit and Save in the block editor handbook for more details on that useBlockProps (hook). 🙂