Check out example codes for "picture html". It will help you in understanding the concepts better.

Code Example 1

<picture>
 <source srcset="mdn-logo-wide.png" media="(min-width: 600px)">
 <img src="mdn-logo-narrow.png" alt="MDN">
</picture>

Code Example 2

<!--When the image is in the same folder as your html file-->
<img src="example.jpg">
<!--When the image is in a image folder-->
<img src="./image/example.jpg">

Code Example 3

<img src="image.jps">
//image.jpg is where you would put the inage source.

Code Example 4

<img src="img_girl.jpg" alt="Girl in a jacket" style="width:500px;height:600px;">

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