When you press google slides it will go to a screen that looks like the picture below.
Google slides is a web based software. You can access it by going to Google Drive. When you get to Google Drive click on new. Next, click Google Slides. Then you are on Google Slides.
Toolbar below
Next start typing if you want to change the text color then click this.
If you want to bold, italic or underline the word highlight it and click one of these icons.
If you want to add a shape, text box, or a line click these icons.
If you want to undo or redo something click these icons.
If you want to add bullit points or a numbered list click these icons.
If you want to delete the presentation you are on or open a new file click this icon
And this will pop up.
To add a link click ctrl + k.
To add a transition click outside of the box and then click transititons and choose one and press apply to all slides.
Now your presentation is ready.