If this is in the US search [your state] extension and you should get their web site, where you can find the location of the nearest branch office. Otherwise tree is a silver maple (Acer saccharinum), trunk cracks visible in first photo make me think it is time for removal regardless of what the source of the red powder is (so far the tuft looks like it consists of roots - here in my area big-leaf maples with rotten trunk sections can be seen having rooted into their own partial remains also). And silver maple is a tall- and wide-growing, big-branched species prone to breakage anyway - it is best used in large open spaces where there is seldom anything underneath it that will be damaged or hurt if the tree starts falling apart.

Just purchased this snd I’m curious if anyone knows exactly what type of cabinet this is and what era it’s from..

It looks more like a fall blooming perennial aster, Symphyotrichum novae - angliae to me. When was this picture taken? Is the plant in the picture above blooming now? It really has all of the characteristics of a Dwarf Fall Aster but they don't start blooming until late August or September. It looks like good ol' Aster 'Purple Dome.'

The cushions are a great idea....but you need somethning to support the cushions. You could have it reseated in split hickory but that would be expensive....and not seen if you want to use the cushions. If it were mine ( and I wish it were!) I would do a rope seat...perhaps not as elaborate as this seat in the link....but you get the idea. https://www.ropesdirect.co.uk/blog/how-to-weave-rope-seats/