With the cost of the SSD and a new graphics card a new PC may be better but without a price range how much better may be up in the air.
Bestbuy has this on sale atm.
https://www.bestbuy.com/site/ibuypower-gaming-desktop-intel-core-i5-9400f-8gb-memory-nvidia-geforce-gtx-1650-super-1tb-hdd-240gb-ssd-black/6400463.p?skuId=6400463&intl=nosplash
Speaking of air, get an air can and blow out that dust! Also something to look into if just upgrading the parts is a larger cpu cooler like a Cooler Master hyper 212 but those 3 things will cost around $250.
Installing them is easy enough. Just watch some YouTube videos on it.