When you open libreoffice impress you will get a dialog to select a templete with a preview select which one you want to use by left clicking and then click open. To add a title to a slide click where it says click to add title.
To open a previous presentation you have been working on press the button that looks like a folder with a piece of paper in it and navigate to the file you want and open it. To save your presentation press the button that looks like a floppy disk.
To type text into a presentation click in one of the boxes for your theme and type in the text with controls for the text on the right hand side. To insert a picture press the button with what looks like a photograph of a tree and select the file you want to insert.
On the left there is a panel showing what slides you currently have in left side of the window. To insert a new slide right click on this panel on the left and select new slide. To delete a slide on the left hand slide right click and select delete slide.
