Wanted to share this really nice icon library site: https://feathericons.com/.
I know that a lot of people fallback to FontAwesome as their go to library for icons. But if you are looking for an open source icon library then https://feathericons.com/ is really amazing.
On their site you can even choose to customize the stroke size of the icons.
There is also https://tablericons.com/ which have even more icons available, also open source, also custimizeable.
Recently Bootstrap published their take at an open source icon library: https://icons.getbootstrap.com/
And finally, if you are looking for a particular brand icon for your next tech stack presentation - take a look at https://simpleicons.org/ - they have more than a 1000 brand logos available.
There many alternatives to FontAwesome, more than I can share here - but take a look at the alternatives.
Feel free to comment if you know of any other open source icons that you would recommend.