Yes, it definitely is a good idea to first sketch out a general overview of how you want your website to look so that when you sit down to code it, you have a guide of what you need to put where.
To clean up your code structure, in the HTML section, click on the arrow and look for a dropdown and click on "TidyHtml’ theres also one for the CSS section. That will make it easier to see what is wrong with your structure and what you need to fix. Under TidyHtml is Analyze HTML…that will show you all the glaring errors. If youre not sure what an error message means, look it up…but most of what I see on yours are missing punctuation and spelling mistakes, proof reading and being careful as you write will help solve a lot of your problems.
While I prefer the route of learning CSS to understand how Bootstrap works, its totally fine to use Bootstrap, just make sure you read the documentation so that you understand what a specific class is for and what you’re actually doing with it…
Really just a matter of…it looks like you’re shooting in the dark. You just need to turn the lights on Start by sketching out your website with a rough idea of where your html elements are supposed to go, W3Schools is a great resource that can help you with that…keep it and the Bootstrap documentation on hand to look up something if you dont know what it means or how to achieve something you’re trying to do.