Can I ask that you do not quote every reply as we have to read the full post to make sure nothing gets missed,, thanks.
To upgrade that PC you are looking at having to replace the CPU, GPU, PSU and the RAM.
Two suggestions that should help improve things somewhat;
Go into the BIOS and enable the auto overclock, being an older board it may be called DOCP as opposed to XMP, this will OC the RAM to its max of 2400MHz which is better than the 2133MHz that it is presently running at, Ryzen CPUs are known for not liking slow RAM and especially the first gen like the CPU that you have, when this computer was put together the RAM selected should have been 2666MHz and not the slower 2400MHz.
Second suggestion will hopefully drop the temps and lighten the load on both the GPU and the PSU, disconnect the second monitor, having a second screen connected apart from stressing a weak PSU can also increase the internal temps by up to 10°C.