Laptop, probably no audio interface, manufacturer install of Win 8 with all the Dell bloatware...
Am I right? That ain't gonna work for intense audio programs like Sonar. Believe me I've tried. You can do SOME stuff but you have to do a whole bunch of fiddling and screwing around to make it work.
You do need to post more details for proper troubleshooting but it is likely going to require purchasing a proper ASIO audio interface.
In the meantime if you are just screwing around on the laptop trying things out and can't be arsed with this type of thing just yet then your best bet... and this is sheer blasphemy for any real audio stuff... is to install ASIO4ALL.
It is GOING to be buggy as hell. You are GOING to experience tons of lags and crashes. You are going to want to toss your laptop through a wall BUT it works better than nothing at all.
Sonar is however a very intense program that will rape your system resources. It works great on a properly set up system but just slapping it on any old laptop... no... just no.
There are optimization things you can do to help as well like using CCleaner and/or Revo Uninstaller to get rid of all the Dell bloatware crap (just don't uninstall anything the laptop needs to actually WORK properly so this takes some time and research).
The absolute BEST thing you can do however is get a PROPER audio interface. You can get simple ones that cost about $150, hook up via USB, use PROPER ASIO drivers (ASIO4ALL is not real ASIO) and make life as an audio weirdo a million times easier. You still have to figure out how to get the system tweaked as best as possible for audio but the difference of interface vs NO interface is night and day.
But more details are needed.
Welcome to the forum.
Cheers.