
Simply put, In Modern pages you can't add classic web parts. You can create a web part page to add that web part.
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I have developed a custom visual web part which i wants to add to modern site page in SharePoint 2019 kindly give me the solution.
Thank You.
Simply put, In Modern pages you can't add classic web parts. You can create a web part page to add that web part.
You could build and deploy client-side web part (SPFx) on the SharePoint modern page.
Here’re some references for you:
Deploy your client-side web part to a SharePoint page
Build and deploy the client-side web part(spfx) in SharePoint