Hi there
Thanks for posting your question in the Lucid Community! You can extend your page automatically by dragging an object into the grey area - or if you're using a template you can extend the page to become larger or smaller. This allows for the flexibility to alter the page to best visualize your work.
When you go to export there are several settings you can choose from to still visualize your chart on the same singular page.
If you'd like to extend your template onto a new page tab you can visit the Template Gallery to insert a new template - which will automatically form on a new tab - or you can copy and paste your current template onto a new tab.
I hope this helps! Let us know about the ideas you come up with!