how to creat new line type in microstation?

In MicroStation, these are referred to as custom line styles, so if you were searching for line types in the delivered help or on this site, you might have not found much. There is some good reference information on custom line styles in Help > Contents, and another place to check out is the Give your files some style with Custom Line Styles - Part 2 AskInga article in the wiki.

thx