My website is set up like this right now "www.mysite.com/blog". But every time i publish a blog post it doesn't go to the blog folder it goes goes to some other folder so the link becomes like this "www.mysite.com/post" instead of "www.mysite.com/blog/post". Is this practice bad for seo? Would google still know i have a blog and that i regularly update it? would it effect my site ranking? if you have any knowledge or evidence please share. I would love to know.
As long as you have linked to the posts in /blog google should have no trouble finding your content, and I don't think that it will care that much. the only "keyword" you are missing out on is "blog".
In which directory the page is does not matter. However, the path to the page from the main page does. I.E. if you have post X positioned two clicks from your main page it is likely have lower SEO value than post Z positioned only one click from your main page. That being said. Avoid too many links on your main page. More than 50 posts linked from the main page may have a negative impact. Remember to give keyworded titles to your posts. I.E. if your post is about samsung tv's and the keyword you want to target is 'cheap samsung tv' they best post name would be /cheap-samsung-tv rather than /samsungtv or simply /cheaptv. These are my experiences.