There is no simple answer to this question since it depends on your blog’s content, frequency of posts, and audience size. Generally speaking, though, a blog should aim to write at least one post per week. If you have more content that you want to share, then you should aim for two or three posts per week. Additionally, if you have a smaller audience, then you may only need to write one or two posts per month.
However, if your blog has a larger audience, then you may be able to generate more traffic and engagement by writing more posts. Ultimately, it is important to experiment and find what works best for your blog.