Being a blogger, first of all, is not at all an easy job. It requires a lot of courage, vocabulary, an ounce to write, use straight words, and confidence of answering back to the people who have some doubts or vouch against what you have written.
When you write something, you should know your capabilities whether you are 100% sure that this topic wouldn't backfire on you in any negative way. You will have to start writing on where your interests are and in which you are really interested then writing on a topic just because it is trending and you think you can write on that.
All the successful bloggers are the ones which are writing on something they like or having podcasts which they speak of something and that is because they love the niche and they love what they are working on. You will have to find something that you are loving it really and start writing, that is when you also will not be out of topics to write on and it will be always going on.
Once you find that then you can do keyword research and other things to make your blog more effective but you need to find that out first as to what exactly you are interested in writing and you will then never be out of ideas.
"All the best"