Hiya, really cool that you want to start a blog! there are many ways to do this however and with the questions you are asking, I am going to assume you are a complete beginner!
1) Short answer for a beginner: No,
Unless you build a blog using more advanced languages like PHP or JS, you're going to have to copy and paste it, Sorry! Alternatively you could look to build your blog using WordPress but you that's a learning curve in itself if you want to go that route. If your goal is to have a very simple blog then this may be a good way to go.
2) I would look up how to use CSS Flexbox and/or CSS grid for this. Without having your website's html and css, it's hard to show you what you need to do.
A little tip: you can go on a website you like the layout of and right click > inspect to see how they achieved it themselves.
3) You can achieve this with Javascript, but I'll leave it to you to research how to do it!

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Hopefully this is a helpful nudge in the right direct! If you need anymore help feel free to reply to this post or DM me