Live streams are always delayed by about 30 seconds. When you are watching a live stream usually what you are seeing happened about 30 seconds ago. Twitch has a 'reduce stream delay' mode in its settings. Go to
https://www.twitch.tv/settings/channel and about halfway down the page there is an option to reduce stream delay which will lower delay from about 5-15 seconds. Personally when I stream the delay is around 18 seconds.
As of your resolution it is on your Video tab under 'output resolution' change that to 1280x720. (leave your base resolution at 1366x768 and select bicubic or lanczos downscale filter)
You are not opening OBS with your GPU you are opening it with your dedicated graphics. Go to:
Nvidia control panel -> Manage 3D settings -> Program Settings -> Select OBS64 from the list (if it doesn't appear on the list then click add and locate the OBS launcher.) Then go down to where it says "Use global setting (Integrated graphics)" and change it to "High-performance NVIDIA processor" then click Apply and restart OBS. This should drastically improve performance.
Your settings are also not very good. You should be using x264 and CPU preset of faster or veryfast (it will use more CPU but get much better quality) Nvidia encoder is good for local recording but bad for streaming.
