A page has several elements to be aware of:
Place your cursor where you want to insert a block element.
Click on the block inserter and scroll through the list to find the element you want, or simply begin typing the element’s name, for example, image. Don’t worry if the block pops up in the wrong place, you can aways move it up or down using the Move up/Move down tool.
You can now edit the options on the page.
Block options are displayed on the right. If no column is visible, select the cog icon at the top right.
By selecting a block’s options icon you can add insertion points before and after, duplicate the block or delete it, along with other options.
The cover image can be replaced and other display elements altered.
Clicking on ‘Replace’ opens up the Media Library, or you can elect to upload a new image.
Once you’ve chosen how many columns you want, the editing page is divided into that number and you can select a block element for each column.
Clicking on it displays the types of block the content can be changed into.
(Note the Columns block, one that I find useful for layout.)
The size of the Heading can be changed.
You either upload a new image, choose one from the Media Library, or insert one from a URL.
If you decide to choose an image from the Media Library, simply click on the image you want and click on ‘Select’.
The image’s options appear along the top of the block and on the right.
You can adjust its alignment, insert a link, crop, add text or a filter over it, replace it and, on the right, you can alter the size.
You can swap the two elements around, left and right.
To embed a Youtube video select the Youtube block and paste your URL into the field and click ‘Embed’.
To replace a video, select the existing video block and click on the Edit tool, then replace the URL with the new one.
To grab the Youtube URL, visit the page on Youtube, click on the share button, then copy the link to paste in WordPress.