RAM is important, but processor too. RAM is where programs write temperary variables, and if they cannot allocate them in it, then the OS will use part of your disk to do so, but remember that it's a lot more slow than RAM, so it will affect the performance or speed.
The important thing is to use FAST devices instead of big capacity. Nowadays the most common processors handle about 2.5GHz within 2 cores, slowest DDR4 RAMs are working at 2.1GHz (data rate > 16GB/s) so they actually work very well together. The problem comes when processor has to load data from disk to RAM (this holy moment when your programs are "Loading..."), when a normal and cheap HDD handles about 80MB/s. It's the famous bottleneck. If you go to the task manager and look for "performance" section, you will see that disk is always exchanging data with the CPU, so if the transfer rate is faster, then the time and speed will be too.

I chenged to SSD in my new laptop and trust me I couldn't believe the difference. First of all: Boot time. In 10 seconds I can see the desktop icons, at 20s I can start using my programs while CPU is still loading things and auto-start programs for 20 more seconds. Heat? Not a little. Sometimes I boot from HDD (my PC has both them, SSD for windows and programs, and HDD for reliable data storage as photos, videos, etc.) just to see how long it takes to start and to feel the hot air blowing from the vent.
When it comes to opening the programs, it's actually faster but not 5 times as good, as happened with the boot. Windows operates smoothly, right-click menus open instantly and programs minimize and move really fast too. It's also quick when turning off.

The disadvantage of SSD is that they have shorter lifetime. A friend of mine had one for 6 months and it stopped working, but other people had them for 2 or 3 years and still working well. I must admit I have an external HDD to backup the SSD data weekly, just in case.

One of the most amazing boosts in your computer's speed can be had from switching to a Solid State Drive.  You can obtain a cheap SSD (120GB SSDs $18.99 on Amazon & eBay),  just for the Operating System and a few frequently used programs.  Then reformat your old Hard Drive as a second Data Drive.   You may want to try out AOMEI Backupper for free, to transfer your files or make a clone before you start. 

I came to say exactly the same. Thank you.

Before you add any RAM, check that it is feasible, both physically (slots on mobo), and supported by the mobo chipset. Some of those chipsets, particularly on consumer machines, have a limit on supported RAM. With more RAM you can run virtualised machines which makes switching between OSes faster if you need to use tools from disparate platforms.

Put your money into an SSD if you don't have one yet. An SSD makes all the difference in the world.

Do you have a SSD already?

how can i tell? sorry, i'm clueless about computers

Does your hard disk drive make noises when you read from or write to it? If yes, then it's not an SSD. Solid State Disks don't have mechanical moving parts, so they are quiet, robust and fast. It's basically like a pendrive. It will make all the disk operations much faster, which means the system will boot faster and the programs will start faster and load files faster.

You proabably don't then. Run whatever program does an inventory of your computer and look up what each of your storage devices is. You probably have a hard disk drive.

Thanks for the tip, my benchmark is Fortnite, because it's easy to run, but i have other goals, like some drone sims. how much faster (graphics wise) will my PC get?

SSDs speed up boot and program loading, but have no effect on CPU and graphics bound programs like games.

i'll have to look into it, thanks!