It is not necessary to add the CSS and JS files both simultaneously but for better usage and as per the rules and regulations of the HTML file you should have to add both the files. So, it'll be better to add both the files simultaneously. Here is the starter template you can use it for add the Bootstrap CSS and JS libraries :
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It is not necessary to add the CSS and JS files both simultaneously but for better usage and as per the rules and regulations of the HTML file you should have to add both the files. So, it'll be better to add both the files simultaneously. Here is the starter template you can use it for add the Bootstrap CSS and JS libraries :
Hope, this will clear your confusion.
Happy Coding!