Not sure exactly what you meant about the fonts but I do routinely install the Microsoft Fonts from my Linux repo whatever system I’m on. It used to be very important when browsing the net as Arial and Times New Roman were ubiquitous. That is less true now, and many sites use their own fonts.
But in office Times New Roman and Arial are still there. Microsoft has moved to newer fonts now like Calibri and Cambrea but this is proprietary. You could try and get your hands on copies of these (relatively easy if you already have windows).
When creating documents you can embed the fonts you used in Libre Office in it to ensure if you send it to someone else it renders as you intended. When you open someone else’s documents you can see what fonts were used and try and install those or ask libre office to substitute fonts you do have for the missing ones. A metric font is a font with the exact same size of characters in terms of character width and height (even if it looks different) - this preserves the layout so if you’re missing a font and have a metric equivalent you can subsitute that font and the document layout should then be preserved.
For Calibri there is a freely licensed Google metric alternative called Carlito. I believe that usually comes with Libre Office but double check. Also Cambria is another common Microsoft font with a free metric equivalent called Caladea that should come with Libre office.
The Liberation fonts commonly found on Linux and Libre office are metric equivalents of the Times New Roman, Arial and Courier fonts if you want to avoid Microsoft proprietary fonts all together.
Finally if you are sending documents to be read and not edited or just to print at another location, then save/export them as PDFs. PDFs will look the same on any device and OS and will print the same from anywhere.
Lastly I would suggest you use a sync service to keep your documents and keep your school docs in folders that sync. Something like DropBox. Microsoft Office uses OneDrive and it is fully integrated which was a game changer when it comes to accessing documents from anywhere but you can do the same with DropBox and Libre Office on other devices to ensure you can get your documents wherever you are and edit them in whatever is available (e.g. a school PC if you don’t have your laptop to hand or your mobile device). Lots you can do with synced documents but you don’t need Microsoft to do it.
Yeah the GUI is horrible with Gimp but it is very powerful software. I’m used to it’s idiosyncrasities but it really needs a GUI refresh. It’s powerful software held back from it’s full potential.