Counsel

You cannot start a company while working in a company that is already in the same domain of work. At the time of joining, the company in the employee contract covers the clauses where they ensure that their employees are not director in any other company or they do not have their nature of interest in any other company which are working in same domain. 

In case you plan to start your business any which ways, then you are inviting trouble for you, and company (previously employed) can counter claim for damages occurred.

While working in a company of same field if any one sets up their company in same domain will be equal to fraud for the company as you may use the strategy and some common sources to get your work done which not ethical also. 

If in case such clauses are not covered in the employement contrct, you need to quit your job if you want to set up your own company in same domain, and after that you can start your own journey by preparing a business model and then incorporate a new company, for this you can “Get a Wazeer” for incorporation and proper compliances.