Welcome to the community.
If you found Linux easy to set up and use 20 years ago - when from my memory - the install process involved a LOT of manual tinkering - it should be an absolute doddle nowadays.
If you can install Windows, then you can just as easily install Linux!
Sure, there are a lot more distros to choose from than there used to be and a lot more desktop environments available; but all modern Linux distros are more or less the same underneath. The only real differences are cosmetic (the default desktop environment, the packaging systems used etc.)
AS wiz pointed out, I'd take a look at starting out with something Debian based (e.g. Debian, Mint or Ubuntu), or if you were using something Red-Hat/rpm-based before - perhaps try something like Fedora or Suse.
The install process is usually:
1. Download a .iso of your chosen distro from their official website.
2. (optional, but advised) Verify the downloaded file using a tool to create an md5 checksum and compare it against the checksum provided by the download site. This helps to ensure that your download is genuine, isn't corrupt and hasn't been tampered with in any way.
https://www.lifewire.com/validate-md5-checksum-file-4037391
3. Burn the .iso to a DVD or a USB stick.
There are various tools available for windows and Linux that can do this. If you are burning to DVD, then you would use your usual DVD burning software.
Here is one tutorial which explains how to burn a Ubuntu .iso image to USB from windows, using a program called Rufus:
https://tutorials.ubuntu.com/tutorial/tutorial-create-a-usb-stick-on-windows#0
NOTE: It doesn't matter that the above tutorial is for Ubuntu - you could substitute the Ubuntu .iso for the .iso for any other distro. The process of creating a bootable USB drive would be exactly the same.
4. Ensure your PC is set up to boot from USB (or DVD) - this typically involves opening your BIOS/UEFI settings and setting the boot device order, to ensure that you are able to boot from the relevant device.
The exact instructions for this step would vary, based on the make/model of your PC.
5. Insert the DVD/USB drive and Reboot into your chosen Linux distro.
Most Linux live/install media will give you the option of to "try linux" without installing anything, or "install linux". Though some only have the "install" option.
If your chosen distro gives the option to "try" without installing, it would be advisable to try that first in order to:
A: Ensure that you can boot to the desktop and that your media burnt/copied cleanly
B: Give your chosen distro a test-drive, familiarise yourself with the desktop environment etc.
If you are happy with your choice and want to install it, reboot again and select the "install" option. (And if you don't like it, perhaps try downloading and burning a .iso for a different Linux distro)
Most distros have user friendly installers that will ask you a few simple questions (about partitioning, time-zone, user-name, password etc) and will automatically install/configure your install with minimal input from you.
The only confusing step might be the initial partitioning related questions. If you understand partitioning, then you should be fine.
If not: at this point, many installers will give you the option to "use the entire disk" - which is a good default for people starting out (unless you want to dual boot, in which case, this is NOT the option for you). The use entire disk option will do exactly that and will overwrite any other OSes on the drive you are installing to.
If you want to dual boot with windows - setting up dual boot is a little more involved. I completely ditched Windows many years ago, so I've never had to do this. But there others here with more experience of that. So if you want to set up dual boot, by all means ask and someone here should be able to help!
But that is it. It's really not any different to installing windows. You'd still have to go through similar things to download and verify a Windows .iso file and burn it to a bootable DVD or USB. You'd also have to ensure that your BIOS/UEFI is set up correctly to boot from the relevant device, before booting into the installer.
It's pretty much exactly the same process.
And once you have installed Linux - you will have access to a huge repository of free software - all downloadable from one place. No more visiting random websites to find the software you want/need.
Most distros ship with a sane set of general purpose software. But anything you feel that you are missing can easily be installed via the built-in package management tools.
And nowadays there are graphical desktop applications that can aid you with package management and installing/upgrading/uninstalling software. You don't have to use commands in the terminal unless you want to. Personally, I find it quicker and easier to do it via the terminal. No waiting for the GUI to load, no clicking through menus or scrolling through icons etc. But some people prefer the graphical/GUI approach!
Again, exact instructions for installing/uninstalling/updating software will depend on the distro you decide to install.
If you have any problems, please feel free to post questions and the rest of the community here will try to answer them as best we can.
We currently only have a small number of regular, active members in the community ATM - all spread through different time-zones - so answers may not be immediate, but we do try to answer all questions.
[edit]
That said, there seem to be a few regulars here today.
A fair few replies came in while I was writing my usual wall of text... XD
[/edit]