Blazor Component

MyComponent01 Page (in Component folder)

<div>
    CurrentCounterValue is @CurrentCounterValue
</div>

@code 
{
    [Parameter]
    public int CurrentCounterValue { get; set; }
}

_Imports.razor

@using myBlazorApp.Client.Component

Index Page

@page "/"

<h1>Hello, world!</h1>

<MyComponent01 CurrentCounterValue="2" />

Sources:

Creating a component