Firstly you will need to be issued with a username and password (your username may be your email address) – this is after extreme vetting to ensure that you are a responsible person who can be trusted to update the website in a responsible manner.
The website uses the very widespread WordPress software, and this means that there are two types of content on the site: “pages” and “posts”. A “page” is intended for permanent reference information – something that you might want to look up any time, for example “how to contact the council” or “a potted history of Brightling”. “Posts” on the other hand are intended for time-bound information such as “Carol singing round the village on 20th December”.
“Posts” appear automatically, blog-style, ie latest first followed by the previous post, then the one before that and so on. You can always see the latest post (and then the earlier ones) at brightling.community/blog, or just choose “blog” from the menu. “Pages” on the other hand, do not automatically appear on the menu, so if you just create a page, it will sit there on the website but no-one will view it because they won’t know it’s there. So in pratice, if you create a page, then you will want to add it to the menu. For example if you created a page on “Local pubs” you could add it to the “Information” section of the menu.
To add a page or a post, visit brightling.community/wp-admin and log on with your username and password. This should take you to the Dashboard and here you will see the vertical menu on the left hand side: select “Posts” then “Add new” (or “Pages” then “Add new”).
That should take you to where you can add your new post (or page). Things here should be fairly self-explanatory. Give your new post (or page) a title, type in or paste in some content, and use the “Save Draft” and “Preview” buttons to see what your new post (or page) is going to look like. It becomes visible to outside users only when you use the “Publish” button (at which point, if it is a post, all the “followers” will get an email.
If you have created a page, and want to add it to the menu, then you need “Appearance, menus” on the Dashboard menu.
If you have just added the page, it should appear at the top of the “Most recent” tab in the Pages pane. Check its checkbox and use the “Add to Menu” button. That will put the item into the Menu Structure but it will appear at the very end, which is probably not what you want. You can use your mouse to drag it to the correct position in the menu.
How to do more advanced things. Given the information that the site runs WordPress software, the easiest way to find out how to do more advanced things is to search for instructions on Google. For example search for “WordPress add an image to a page”, and so on. However, if you get stuck, local experts will be happy to help.