So, I'm currently attempting to create a homebrew race and one of their features is that they get to choose two proficiencies from a list of four (basically the Lizardfolk's Hunter's Lore feature) and I'm having trouble doing that.  I know that it's in modifiers somewhere under Proficiencies, but I'm not seeing a subtype that lets me give the player a choice other than choosing from a list of ALL the proficiencies rather than just a select few.

You have to implement it using options. These are the steps for subclasses, but its the same for races:

https://www.dndbeyond.com/forums/dungeons-dragons-discussion/homebrew-house-rules/66803-adding-choice-of-skill-proficiencies-to-homebrew?comment=10

You will have to create four Options attached to the racial trait, one for each of the four Skills, and attach the Modifier for each proficiency to its corresponding Option. If you need any help with setting up the Options, I gave a full walkthrough with images in the Subclasses & Races FAQ #1: (https://www.dndbeyond.com/forums/dungeons-dragons-discussion/homebrew-house-rules/131411-a-homebrewers-how-to-faq).  

Awesome.  How would I make it so that I can choose two instead of just one?

Quote from andrewjking456 >>

Awesome.  How would I make it so that I can choose two instead of just one?

 
I explained that in the walkthrough in that FAQ too.

Which part?

Quote from andrewjking456 >>

Awesome.  How would I make it so that I can choose two instead of just one?

 

 In the "Character Levels Where Options Known" box for the main trait, put 1,1

Thanks a ton for the help you guys.  Really appreciate it.

Quote from andrewjking456 >>

Which part?

 
The Subclasses & Races FAQ #1. That whole entire entry is a walkthrough on how to implement Options in features & traits.