Just for the stuff that I mentioned above it is possible (gpu, cpu, ram, motherboard), but when you also need a screen, pc case, fans, power supply,… then it will get a little bit tricky 
I would also recommend you to take a look at some other setups which have been posted this forum and answerhub -> just search for them, then you can get a pretty good overview of which specs you will need. And another small hint: don’t buy all the stuff at just one supplier, search for the best offers all over the internet. Of course it will take longer until you have everything together, but you will save a lot of money