Fonts can actually be a bit complicated, though it's easier today since you don't have to also worry about Postscript. You'll use a particular font as part of the design for your work that's printed or published online [i.e. website/blog]. Google for specifics like setting Kerning, Tracking, Leading etc. if you want to really get into it, & there's plenty of info online regarding web fonts too.
Today's GOTD provides OTF & TTF files -- so what gives? TTF, or TrueType fonts are what Windows used originally, while those needing more than what TrueType could deliver relied on Postscript fonts [some may remember Adobe Type Mgr.]. Eventually Adobe & Microsoft came together to create the OTF font format that blends the two together. So, in a nutshell, use OTF unless [usually older] software complains or refuses to cooperate, & then use TTF, but don't have both versions of a font installed or activated at the same time.
Now some people will just go ahead and install the 100 fonts we're given today, but that's kinda silly IMHO... for general day-to-day use you'll probably only use one or a few fonts, and it not only slows things down loading all those fonts, it makes it a PITA trying to find your normal one or two. That where Font Managers come in, and a decent choice for a free one is FontBase. fontba[.]se/
It's a bit on the bare side, and maybe not the most intuitive design -- you have to play with it a bit to get the hang of things -- but it works well enough & as I said, it's free, though a paid version is available. Running the installer FontBase defaults to adding the program to the user folder -- if you want the roughly 200MB app in a more normal location like Program Files you can choose that new location, but you have to run the setup file as admin to do so. Installation adds 2 registry keys, one for the app & one for uninstall, but those keys did not use the app's name, using [HKEY_CURRENT_USER\ Software\ ffc1e284-e25b-515d-b453-93eb9fe955eb] instead. A copy of the setup file is added to Users\ [UserName]\ AppData\ Local\ fontbase-app-updater\, and a folder with settings and cache is added to Users\ [UserName]\ AppData\\ FontBase\.
TO add today's collection put the un-zipped folder wherever you intend to keep it, then hit the + button on the lower left. FontBase does Not include the fonts that are installed with Windows & by your installed software, but does list Google's collection & whatever other collections you add. You get a quick view of the fonts, and some limited data on the characters included -- you may still need to use Windows Character Map. If it displays just one type of font [OTF/TTF] you can right click that font & select activate -- if it shows both you want to click show family, which shows up when you mouse-over the font's display, then select the OTF or TTF version you want to activate. Once activated it will show up for example in Notepad as a font choice -- do the same process selecting deactivate to turn that font off.