The Medic archetype has an issue at 4th level where Doctor’s Visitation is showing up but Treat Condition is not. The Treat Condition feat is the prereq for Holistic Care at 6th level and Preventative Treatment at 8th level.
Thanks for the report! Seems to be something fishy going on there.
While we fix what’s happening here, I’ve discovered a short-term solution so you can keep making your character:
- Click “Filters”
- Go to the “Subcategory” filter
- Add “Medic”
- Save filters
You should see Treat Condition appear!
We’ll get it sorted so you don’t have to take these steps, though.
Aha, we’ve solved it!
Treat Condition is an archetype skill feat, so you can choose it when selecting a skill feat, instead of a regular skill feat.
There are a number of archetypes that have this same issue. As Free Archetype is an incredibly popular house rule there needs to be a workaround here because now the free feats have nothing to spend on at 6th level, as an example, and many GMs house rule that a class or archetype feat is more valuable than a skill feat so they should be allowed to spend one on an archetype skill feat.
This could be another option to select at character creation just like Free Archetype.
There are a few archetypes like that, but you can just avoid taking them early on. And for Medic you can grab it on L2 with FA, put Treat Condition in your Skill Feat slot on L4, put Doctor’s Visitation in FA slot on L4, and be free to pick another Archetype on L6. It is honestly one of the easiest and most permissive Archetypes in the game.
But yeah, I wouldn’t mind further expansion on this variant rule. Like “Free Archetype (unlimited)” or something.
That would be a question for Paizo! We don’t create our own variant rules. 
If your GM allows it, you can go into the “Filters” anytime you’re selecting a feat to change what feats you have available to you outside of the standard rules.