I want to extend WebSecurityConfigurerAdapter but it had been deprecated - spring

Question

I'm trying to code a website using spring boot(security, jpa, web...) and i'm following this tutorial.
And in the minute : 1:05:25 , he needs to extend the WebSecurityConfigurerAdapter, but it had been deprecated in the last spring boot versions, so he changes the version in his "pom.xml" from :
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.7.3</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
To :
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.6.5</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
Then he saves all and updtaes the project. And when I do the same I get errors in my pom.xml file in the parent tag:
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.7.3</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
with the error : Coul not read maven project ...
And I get an error in this dependancy :
<dependency>
<groupId>com.mysql</groupId>
<artifactId>mysql-connector-j</artifactId>
<scope>runtime</scope>
</dependency>
The error is :
3.0.0+
The <dependency> element contains information about a dependency of the project.
Source: maven-4.0.0.xsd`
I also get this error in my console :
APPLICATION FAILED TO START
***************************
Description:
Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.
Reason: Failed to determine a suitable driver class
Action:
Consider the following:
If you want an embedded database (H2, HSQL or Derby), please put it on the classpath.
If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are currently active).
While in the video, he doesn't get errors at all.
So I would like to solve the problem by modifying something in my pom.xml and keeping that application.