For RAM you will need another DDR4-2400 DIMM. However, there are 2 says of doing this. Just going with 1 stick of 8GB doesn't assure your system will be stable. Using 2x 8GB kit will assure stability. For the GPU the fastest 4GB is a GTX 1650. It is also low profile so it would give you options if you need a low profile GPU. There is also a very slim outside chance that with a BIOS update you could upgrade the CPU to a Ryzen. The motherboard is AM4 so it might work, but it is a slim chance. PCPartPicker Part List
I see. I'd just end up sinking more money into it by trying to make it into something usable rather than just making a new PC. If that's the case, could you point me in the right direction of some parts or even a parts list?