I have apache, php, mysql, etc. setup on my 16.04 linux ubuntu server. I can access the webpage I have createdin /var/www/html/index.php using 10.0.0.8 now I want to use a domain name or even an IP address to access the server off of a local connection and on another internet connection. What do I have to do to do this I have no clue and I have no clue what to google to find out.
You should buy a domain name from a provider such as GoDaddy and assign it to your public IP address. Visit a public "What's my IP?" site to find your public IP address or look in your router settings to see what address was provided by your ISP. You'll probably have to enable port forwarding on your route for port 80 to 10.0.0.8.