It took me a year to eligible for youtube monetize for my very first channel. Here is what I can recommend (it not true for all but for me it totally right).
1. Research keyword trend on Google keyword planner. Choose medium and low competitive keyword only. Create video base on that trend.
2. Optimize your video on Youtube by add right keywords from #1 on your video before publish.
3. Create attrative thumbnail, this is very easy.
4. Share it on relate blog, fb group, forum, ... as much as possible.
5. Create shorter video from original one and upload on Youtube Short, Tiktok. Alway put a link to subscribe your channel on first comment and description.
Never stop learning , don't hesiate to investigate on buying courses to improve your knowledge. You will get Youtube silver button very soon.