I need to bulid feasibility of small computer company assembly and sale can you help me to do that

Sure, we can advise you as much as we are able. What would you like to know?

design plan , put strategic plan and how to calculated stamated value of project

http://www.sba.gov/ and SCORE | Counselors to America's Small Business | SCORE are excellent sites where you can find sample business plans and other types of documents that you might need to start a business. You could find business plans and documents that are like what you might want and then tailor them to suit your needs.

As far as pricing the product, you could try the following search and find similar items and make comparisons and then come up with your own competitive prices.

Wholesale Computers - Google Search

At least those are some ways that I can think of right now that might be helpful to you. Hopefully, others will come along and also offer their advice.

Feasibility is based on two major things:

First, financial feasibility. If the money isn't there than it is not feasible. Granted, the plan can be leveraged through a bank or one could get seed capital for private equity in the business but this is a long road to travel.

Second, market feasibility. You can't create a market to satisfy your needs, you need to create a product that will satisfy the market's needs. This requires a lot of research. I would take the advice in the previous post and go to SCORE | Counselors to America's Small Business | SCORE. I love the site. I would also look up the location of the local SBDC (Small Business Development Center) and see if they have any information you could use. Their services are free but they are terribly busy.