You can change the default colors, fonts etc and apply colors and fonts of your choice. You can select any line and then apply a new font or color. Similarly, you can change fonts by selecting a line and changing the font using the pull down font menu at the left top corner of your screen. Select a speed. Do NOT get carried away.
Some transitions are slow and too many transitions distract the audience.
Keep it simple. First slide the slider bar on the right edge of your screen all the way to the top. Go to that slide. Select the text you want to build. Try out a few.