Please help an old newbie

New to all things Website, not just WordPress. I have no idea how to insert the “Link to the page you need help with” box above. Shouldn’t matter since there’s nothing there but some failed attempts to insert blocks. Studied the How to Set Up articles and the block editor documentation, but can’t get past Square One. I can add an image block but that’s all. The handle described in the manual does not appear. I can rezize it but not move it around.

When I try to add a paragraph block, it just disappears. I gave up on WordPress and built a starter site in Hostinger Site Builder only to find its capabilities too limited, and their support team recommends WordPress. When I try to do their suggestions, there’s always something I need to know first. I could learn by trial and error, poke and hope, if only I could get the blocks on the page to play with them, but I can’t understand and follow the instructions. For example, I am still not clear on whether the Insert Block button is for inserting a new block onto the page, or for inserting something into a block that’s already on the page.

I have read over and over about themes and still don’t know what they do. Would the wrong theme make the block editor behave different than the instructions say? How do I pick the right theme? How do I even know what the right theme even is when I don’t even know what a theme even is? Do I really even need a theme?

I don’t even know how to pick a “topic tag” for the help forum box below. Though I have a vague idea what they’re for, I wouldn’t know which ones to pick, even if I could find the topic tags listing. Is there any help for someone who has read and re-read the instructions but still can’t get a website going? Thanks