What you need is available several ways.

1. Place your cursor anywhere in the paragraph you wish to indent. On the Home tab, click on the small arrow in the bottom right corner of the Paragraph section, or, simply type Alt+O,P (hold down the Alt key while pressing O, then P). Either will bring up the Format Paragraph dialogue box.

Under Indentation, enter the amount of indentation you want and click OK. You can also select multiple paragraphs and then do this.

2. If your top and left side rulers are not showing, display them by either checking the Ruler box in the Show/Hide section of your View tab, or by typing Alt+V,L. With your cursor in the relevant paragraph, or with multiple paragraphs selected, click and drag on the little square under the lower pentagonal margin marker aligned with the left margin, dragging it to the desired indent position and then releasing the mouse button.

You may also wish to look up Styles at some point, so that you can set a preset with this indent and redo it quickly when you want it.

I hope this helps.