SfRibbon (Main Container)
├── RibbonFileMenuSettings (Optional File Menu)
└── RibbonTabs
    └── RibbonTab (Home, Insert, Design...)
        └── RibbonGroups
            └── RibbonGroup (Clipboard, Font...)
                └── RibbonCollections
                    └── RibbonCollection (Row/Column Layout)
                        └── RibbonItems
                            └── RibbonItem (Button, Dropdown, etc.)

@using Syncfusion.Blazor
@using Syncfusion.Blazor.Ribbon
@using Syncfusion.Blazor.SplitButtons

<div style="width: 100%">
    <SfRibbon>
        <RibbonTabs>
            <RibbonTab HeaderText="Home">
                <RibbonGroups>
                    <RibbonGroup HeaderText="Clipboard" Orientation="Orientation.Row">
                        <RibbonCollections>
                            <RibbonCollection>
                                <RibbonItems>
                                    <RibbonItem Type="RibbonItemType.SplitButton">
                                        <RibbonSplitButtonSettings Content="Paste" IconCss="e-icons e-paste" Items="@pasteOptions">
                                        </RibbonSplitButtonSettings>
                                    </RibbonItem>
                                </RibbonItems>
                            </RibbonCollection>
                            <RibbonCollection>
                                <RibbonItems>
                                    <RibbonItem Type="RibbonItemType.Button">
                                        <RibbonButtonSettings Content="Cut" IconCss="e-icons e-cut" OnClick="@OnCut">
                                        </RibbonButtonSettings>
                                    </RibbonItem>
                                    <RibbonItem Type="RibbonItemType.Button">
                                        <RibbonButtonSettings Content="Copy" IconCss="e-icons e-copy" OnClick="@OnCopy">
                                        </RibbonButtonSettings>
                                    </RibbonItem>
                                </RibbonItems>
                            </RibbonCollection>
                        </RibbonCollections>
                    </RibbonGroup>
                </RibbonGroups>
            </RibbonTab>
        </RibbonTabs>
    </SfRibbon>
</div>

@code {
    private List<DropDownMenuItem> pasteOptions = new List<DropDownMenuItem>()
    {
        new DropDownMenuItem{ Text = "Keep Source Format" },
        new DropDownMenuItem{ Text = "Merge Format" },
        new DropDownMenuItem{ Text = "Keep Text Only" }
    };

    private void OnCut(MouseEventArgs args) { /* Handle cut action */ }
    private void OnCopy(MouseEventArgs args) { /* Handle copy action */ }
}

<SfRibbon>
    <RibbonTabs>
        <RibbonTab HeaderText="Home"><!-- Home commands --></RibbonTab>
        <RibbonTab HeaderText="Insert"><!-- Insert commands --></RibbonTab>
        <RibbonTab HeaderText="Design"><!-- Design commands --></RibbonTab>
    </RibbonTabs>
</SfRibbon>

<RibbonTab HeaderText="Home">
    <RibbonGroups>
        <RibbonGroup HeaderText="Clipboard"><!-- Copy/Paste items --></RibbonGroup>
        <RibbonGroup HeaderText="Font"><!-- Font items --></RibbonGroup>
        <RibbonGroup HeaderText="Paragraph"><!-- Alignment items --></RibbonGroup>
    </RibbonGroups>
</RibbonTab>

<SfRibbon>
    <RibbonFileMenuSettings Visible="true" MenuItems="@fileMenuItems">
    </RibbonFileMenuSettings>
    <RibbonTabs><!-- tabs here --></RibbonTabs>
</SfRibbon>

<RibbonItem Type="RibbonItemType.ComboBox">
    <RibbonComboBoxSettings DataSource="@fontFamilies" 
                             FieldSettings="@fieldSettings"
                             AllowFiltering="true">
    </RibbonComboBoxSettings>
</RibbonItem>

<RibbonItem Type="RibbonItemType.GroupButton">
    <RibbonGroupButtonSettings Selection="GroupButtonSelection.Single" Items="@alignmentOptions">
    </RibbonGroupButtonSettings>
</RibbonItem>