how to link mysql data base with my localhost website

i am beginner with creating websites i have already created a website by html and ccs and also i created the database by my sql queries now still link the database with my website in xampp server so i have no idea how to do it i search google i found one explanation that told me to create db_cinnection.php file in htdocs where my website files located and import my database file to myphp admin i did all these steps i don't know what is the next step should i write any codes in each page code of my website or not i hope someone help me i will really thankful for him/her all the best