Thank you! I guess it is time to hire an electrician.
Let me save you some time, and potentially some consultation money,
An electrician is going to turn down this work, for several reasons:
1. This is not a grid-tied inverter. It does not supplement power, like those retrofitted into houses by the professionals (SolarCity, etc). It is not possible to connect it to an existing electrical panel - at minimum, you would need a second "off-grid" breaker box.
2. This is an off-grid inverter. Are you in the US? It does not have the regulatory certifications for safety. An electrician risks their license if they installed it.
3. Other technical limitations. For example: This is a 120v single inverter - you need at least 2 for 240v loads in split-phase. Also, a single 3000W inverter is going to be too small to power a whole house.
I don't wish to sound discouraging, but this is complex stuff with a lot of safety concerns. Even for someone with advanced electrical/electronics experience, it is not easy to plan and build a system. It is cool that you found the inspiration to try something like this, and this forum is a good place to acquire more knowledge. That being said, I would recommend you stick the extension cord outlet, as seen in Will's content, to power a couple things directly. If you take notice, all of Will's videos and reviews show these inverters being used off-grid - in a trailer/shed/RV/outdoors.