I’m old and still not sure how hashtags work even after your e ply. Help me

You put hashtags in the title or description of your YouTube video. Hashtags are used to categorize your YouTube video and help people find it in YouTube search. You can use up to 15 hashtags total in the title and description of your YouTube video. If you use more than 15 hashtags all your hashtags will be ignored by YouTube. Hashtags start with a number sign # an example of a hashtag is #cheese. The first three hashtags you use have the most weight and SEO relevance in YouTube search. If you don’t add any hashtags to the title of your video YouTube will add the first 3 hashtags you use under your videos title on the video page.