how do i wrote interpreter?

I want to implement a scripting language in my project.

I don't want to use Lua, even though it's the easiest way I know how.  Instead, I want to write my own scripting language interpreter into my program.

I've a B.S. degree in Computer Science so I know most of the fundamentals, but not the advanced practicalities.  For example, I can probably write up a formal grammar for whatever scripting language I wish to use -- but ... then what?  How do I apply that knowledge, to what I wish to do?

Any good sources on this subject that isn't targeted towards Ph.Ds with Masters Degrees, but good enough for someone with a B.S. degree level of education?

The most important question here is why you don't want to use Lua? Why are you reinventing the wheel?

There are several decent compiler books that are now out of print and are thus available on the Internet for free from their authors. Thirty seconds of searching will turn them up.