To merge projects, we need to select at least 2 files, then choose whether to combine their models, light objects, scenes, etc. The checked items will be retained in the merged result; while unchecked ones will be removed.If we check the same option for multiple projects at the same time, only one copy of the identical parts of the scene will be retained; different parts will be added automatically. For example, the same light exists in both projects. If the light is checked in the merge option, adding the parameters of the light in the project will overwrite the light parameters in the previous project.If we check the same option for multiple projects at the same time, different parts will be added automatically.