any console commands to improve fps?

It depends on what causes the fps issues. Do you have constantly low fps (in this case it's caused by your CPU and/or graphics card), or do you get low fps after some time (in this case it's most likely caused by insufficient memory)? What hardware do you have exactly (CPU, graphics card, RAM)? Alternatively you can open console and type "report", then a file called "report" (followed by a long number) should appear in your game directory. Please open this file with a texteditor and post the content here.

You should also lower your graphics settings, disable all effects (especially "Light scattering" and "Ambient occlusion" have a big impact on performance), and reduce the view distance (especially the detail distance).