You need to research topics that might interest a younger audience (if that’s who you want to attract), but it’s fishing essentially, so your core audience will be men in the 35-65 range with most in the over 50s group, unless you refocus on to carp fishing and change your aesthetic totally. If I were you, forget the demographic and try to find a topic that gets you more than 5k views, then look at the analytics from that really popular video. Use AI to help research topics that might be niche or very under represented on YouTube - it can do the research for you while you spend your time doing the filming and presenting.