In SitePad, the widgets available in the sidebar depend on:

- the theme you are using, and

- what SitePad itself supports (it’s more limited than WordPress).

You cannot add arbitrary new widgets like in WordPress. The documentation often shows widgets that are:

- theme-specific, or

- available only in certain SitePad versions / templates.

- What you can do:

- Use the existing widgets shown in your panel.

- Add a Custom HTML widget (if available) to embed code (e.g. scripts, iframes, simple embeds).

- Change to a different theme that exposes more sidebar widget areas.

What you cannot do:

- Install plugins to add widgets.

- Create native custom widgets via PHP.

If you want, tell me:

- which SitePad version you’re using

- which theme