As everybody’s needs, data and theme are different, a generic video is not as useful as it might sound.
Have you made a form yet? If not, can you let me know what theme you are using and send me a live link/URL to your (search) page so I can take a look? The search page is usually where you want to place the search, and possibly where you want to see the results (not always the same page).
The easiest way to place a search form on the page is to use Appearance -> Widgets and place our search widget in an available sidebar.
I need to know what you are searching (post type) and do you want a text search category search, etc.?
Knowledge of PHP is not necessarily required, depending on your choice of theme.
Some themes have page builders supplied with them, or often built in, to make the process potentially a lot easier.
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