Virtually all of my songs in the showcase are MIDI so you might want to give a listen.

I will not repeat everything that already has been said but I will give you some free options for better MIDI sounds:
1-Get Coolsoft soundfont player and Timbres of Heaven soundfont as Mike suggested

2-Get the Free Kontakt player:

https://download.cnet.com/Kontakt-Player/3000-2170_4-10161711.html

And maybe some free Kontakt sounds to augment it:

https://www.productionmusiclive.com/blogs/news/top-10-free-kontakt-libraries

https://www.flstudiomusic.com/2017/03/38-best-free-kontakt-libraries.html

3-Get the free Sampletank 3:

https://getintopc.com/softwares/audio-processing/sampletank-vst-free-download/

Note that there are a lot of sounds for Kontakt but be very careful if you purchase some as some are for the full version of Kontakt only and will not play in the player. This is always marked on the sites so be sure to look for it.

Also note that there are tons of free soundfonts for any free soundfont player.

I would start with the soundfont player and add Kontakt and Sanpletank once you get the hang of MIDI.

If you need any help we are here for you so just ask.

Good luck.

When you are at the checkout line and they ask if you found everything say "Why, are you hiding stuff?"

64 bit Win 10 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware