Hi,
there are plenty of root tutorials by searching in google: root blu dash jr
There is a link for example: http
/androidgoroot.com/how-to-root-blu-dash-jr-3g/
But I would recommend you to do some investigation between the sites you find in order to see which is the best way to perform root, because it varies from phone to phone. Also, take into consideration that you could end bricking your phone.
Also if you want to remove the bloatware, there is another way that is disabling apps (without root). Go to settings, applications, all applications, enter in the "non wanted" application and press "disable".
Just a quick comment, removing using root or disabling apps (without root) won't give you more internal space. So if you want to have more space for installing apps, you should try using a sd card and move the apps.
Regards