Check out example codes for "how to change font in css". It will help you in understanding the concepts better.

Code Example 1

p {
  font-family: "Times New Roman", Times, serif;
}

Code Example 2

p {
  font-family: "Times New Roman", Times, serif;
}

p.normal {
  font-style: normal;
}


p.italic {
  font-style: italic;
}


p.oblique {
  font-style: oblique;
}

Code Example 3

/* Answer to: "default font family css" */

/*
  The font family of a text is set with the font-family property.

  The font-family property should hold several font names as a
  "fallback" system. If the browser does not support the first font,
  it tries the next font, and so on. 

  Start with the font you want, and end with a generic family, to let
  the browser pick a similar font in the generic family, if no other
  fonts are available.

  For more information, go to:
  https://www.w3schools.com/css/css_font.asp
*/

Code Example 4

p {
	font-size: 150% /*px, cm, in, etc.*/; 
}

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