I have a problem to sale electric lamp and LED bulb. So I want to know how many lumens equal to how many watts?
This depends completely upon what method is used to convert the electrical energy into light. Is it an old Edison bulb (incandescent), florescent, LED, something else?
It will also vary significantly within each type. Not all LED bulbs are equally efficient. There simply isn't any direct conversion. You need to check the specs for the specific bulbs you are comparing.