Site domain changed, wordpress no longer works

I had a blog for a client at a domain name which has now changed. I moved the blog folder into the folder for the new domain name on the server. However the blog now comes out as a long text file, and no longer works in with the database etc. You can see it here: https://www.mynaxyoga.com/wordpress/ I have actually forgotten how I installed this blog in the first place. Anyway I would like to have the content and settings kept as they were if possible, rather than install a new blog. Is there a config thing which will point the system to the new spot?
thanks