Need help with placement in sidebar

Hello,

My site is https://www.parnellpainting.com I am using Sea shore 1.0 as a theme.

I have several different pages in the sidebar because that is the only way I could figure out how to have posts that didn’t just run in succesion all down one page for the customer to look at. Was this what I shoud have done to get around that?

The other section on my sidebar titled articles are links to articles on other websites. I have also written some of my own articles. I wanted to have those listed with together with the other articles, but there seems no way to do this. So every time I write something myself I end up creating another page, such as the ones called Choosing a paint sheen and choosing a colour. Is it possible to have links to those with the other article links?

I might be making this whole site in a strange way because I am new to wordpress and just don’t no any better. So feel free to throw suggestions at me if you have them.

Thank you for your help