looking for a tool?!

hey guys, im looking for a tool that can help my find youtube comments in my niche ?
ex: someone posts a comment on yt like this
"i whant to buy bitcoin but i dont know how"
does such a tool exist? so i can get notifications when people ask something about my niche? if yes how does it work?

To find older comments you could use a google search string, I'm not sure the exact best one but something like site:youtube.com and then a search function for 'I want to buy bitcoin', for exampe intext:
Look up google search strings online and you can easily find the best one for you - https://ahrefs.com/blog/google-advanced-search-operators/

This only works with indexed pages that are a bit older though, so to find the latest comments you should look into setting up some sort of alerts.
I don't know how to do that and I hope someone will reply with a good way, as it's of high interest to me as well.

The final thing you can do is lurk channels in the crypto niche, or again, find such channels with search strings and post the comment you need by yourself, get a friend to post the reply you need or just simply use a vpn with different ips for accounts. You might also need to do other random comments with these accounts to not get shadow banned (simulate a regular user).

At a first glance it's not possible to monitor all YT. It's too big.
Focus on main KWs, videos and channels. Monitor their comments sections (manually or custom software). I'm not aware with any tool but think it's possible to develop one.