Those are really good questions, an easy way to asertain the information you require is to locate your chipset information. The chipset on the motherboard determines a lot of things, one of those things being the amout of RAM that you can install and utilize. There is also a helpful program called CPU-Z which will give you a lot of useful information. But, if you are feeling brave, you can attempt to remove the bottom cover and locate the RAM yourself. Just by looking you should be able determine if it is soldered or not.

I know you said you have tried basic troubleshooting, but did that include attempting to power on the device by holding down the power button and also one or both of the volume buttons? Also, how old is the tablet? Do you know which Android operating system it is running on? I'll try to help you as much as I can.

First off this is a super well documented question, second to get the obvious out of the way, have you enabled "assistive touch"? As you may know, Assistive touch will place a virtual, yet fully functional home button on your home screen. The button itself is not super difficult to replace. Depending on the model it may be held in place by a small metal bracket and two small screws. Getting the iPad open safely is another obstacle. I would definitely recommend using assistive touch as it is the less invasive option. I apologize I cannot help further.

What basic troubleshooting steps have you taken? Have you reseated the RAM? Tested the power supply? Ensured the proper voltage setting is selected on the power supply if applicable? Do you have any tools to test with?