Hello.
Tell me, please, with the help of which you can implement such previews or just blocks with text, the latter would probably be even more suitable.
CMS: joomla 3
Try to create a module in the "components" tab, using the standard set of modules to display this or that information.
If it does not work out, then you can try to make an HTML module in the same "components" and insert the code there according to your needs (accordingly, the code must be laid out)
If both of the first options are not suitable, then try using ready-made solutions from the Joomla extensions directory .