Column Width

This web site builds the control from code behind but you could also grab it from the toolbox.

sample image

Code behind

using System.Windows.Forms;
using LiveChartsCore;
using LiveChartsCore.SkiaSharpView;
using LiveChartsCore.SkiaSharpView.WinForms;

namespace WinFormsSample.Bars.Spacing;

public partial class View : UserControl
{
    public View()
    {
        InitializeComponent();
        Size = new System.Drawing.Size(50, 50);

        var values = new double[] { 20, 50, 40, 20, 40, 30, 50, 20, 50, 40 };

        var series = new ISeries[]
        {
            new ColumnSeries<double>
            {
                Values = values,
                Padding = 0,
                MaxBarWidth = 99999
            }
        };

        var cartesianChart = new CartesianChart
        {
            Series = series,
            Location = new System.Drawing.Point(0, 0),
            Size = new System.Drawing.Size(50, 50),
            Anchor = AnchorStyles.Left | AnchorStyles.Right | AnchorStyles.Top | AnchorStyles.Bottom
        };

        Controls.Add(cartesianChart);
    }
}

Articles you might also find useful:

Cartesian chart control
Column series properties