My first blog(I'm a blogger now, yeah!!)

I don’t know what to say, but this is just the beginning of my blogging career. First, I want to ask for some help. What should I do, and where should I begin? I know I need to be unique to make a meaningful impact in the vast sea of internet blogs. It would be really helpful to know where to look for blog ideas. Is it just about doing whatever you want, even if there are thousands of blogs already teaching the same thing?(Heavily inspired by original one, I guess?)
Also, how can I ensure I’m not plagiarizing someone else’s content or ideas, especially if I'm writing on the on the same topic? Do I need to dive deep into copyright laws, or is surface-level knowledge enough? I have so many questions, and you might call me a novice (which I am). But hey, everyone has to start somewhere, and this is mine I guess!