Change the connection string of the auto generated WEB API authentication? - sql-server

Question

I created a WEB API project that involves individual user accounts authentication. I have already an existing database with additional tables, how can I link my database to this project instead of creating a new one?
I tried to add an ADO entity model but still it can't reach my database.
What should be done in this case?
This is the web.config file :
<?xml version="1.0" encoding="utf-8"?>
<!--
For more information on how to configure your ASP.NET application, please
visit
https://go.microsoft.com/fwlink/?LinkId=301879
-->
<configuration>
<configSections>
<!-- For more information on Entity Framework configuration, visit
http://go.microsoft.com/fwlink/?LinkID=237468 -->
<section name="entityFramework"
type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection,
EntityFramework, Version=6.0.0.0, Culture=neutral,
PublicKeyToken=b77a5c561934e089" requirePermission="false" />
</configSections>
<connectionStrings>
<add name="DefaultConnection" connectionString="Data Source=
(LocalDb)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\aspnet-
FlutterBackend-20200123055259.mdf;Initial Catalog=aspnet-FlutterBackend-
20200123055259;Integrated Security=True" providerName="System.Data.SqlClient" />
</connectionStrings>
<appSettings></appSettings>
<system.web>
<authentication mode="None" />
<compilation debug="true" targetFramework="4.7.2" />
<httpRuntime targetFramework="4.7.2" />
</system.web>
<system.webServer>
<modules>
<remove name="FormsAuthentication" />
</modules>
<handlers>
<remove name="ExtensionlessUrlHandler-Integrated-4.0" />
<remove name="OPTIONSVerbHandler" />
<remove name="TRACEVerbHandler" />
<add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="*" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
</handlers></system.webServer>
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="Microsoft.Owin.Security"
publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="0.0.0.0-4.0.1.0" newVersion="4.0.1.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="Microsoft.Owin.Security.OAuth"
publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="0.0.0.0-4.0.1.0" newVersion="4.0.1.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="Microsoft.Owin.Security.Cookies"
publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="0.0.0.0-4.0.1.0" newVersion="4.0.1.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="Microsoft.Owin" publicKeyToken="31bf3856ad364e35"
/>
<bindingRedirect oldVersion="0.0.0.0-4.0.1.0" newVersion="4.0.1.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="Antlr3.Runtime" publicKeyToken="eb42632606e9261f"
/>
<bindingRedirect oldVersion="0.0.0.0-3.5.0.2" newVersion="3.5.0.2" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Optimization"
publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="0.0.0.0-1.1.0.0" newVersion="1.1.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="WebGrease" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="0.0.0.0-1.6.5135.21930" newVersion="1.6.5135.21930" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed" />
<bindingRedirect oldVersion="0.0.0.0-12.0.0.0" newVersion="12.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="0.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="0.0.0.0-5.2.7.0" newVersion="5.2.7.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="0.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Http" publicKeyToken="31bf3856ad364e35" culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-5.2.7.0" newVersion="5.2.7.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Net.Http.Formatting" publicKeyToken="31bf3856ad364e35" culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-5.2.7.0" newVersion="5.2.7.0" />
</dependentAssembly>
</assemblyBinding>
</runtime>
<entityFramework>
<defaultConnectionFactory
type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
<providers>
<provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
</providers>
</entityFramework>
<system.codedom>
<compilers>
<compiler language="c#;cs;csharp" extension=".cs"
type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.CSharpCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=2.0.1.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" warningLevel="4" compilerOptions="/langversion:default /nowarn:1659;1699;1701" />
<compiler language="vb;vbs;visualbasic;vbscript" extension=".vb" type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.VBCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=2.0.1.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" warningLevel="4" compilerOptions="/langversion:default /nowarn:41008 /define:_MYTYPE=\"Web\" /optionInfer+" />
</compilers>
</system.codedom>
</configuration>
I want to apply the authentication actions on my own database instead of the one autogenerated by the asp.net