New user here. I used it for running one workout so far and I like it. Is there a way I can browse available workouts that I might want to do the next day? If so how and where exactly do I do that? Also if I see a workout can I add it to a schedule?
To find workouts, you can go to the little icon on the top row that has the little vertical bars (possibly on a clipboard). There you can see collections of workouts, your custom workouts, all workouts, and Training Plans- these will all be on the left-hand side.
When you get to a list of workouts, you can sort them by duration and effort.
It’s a little trickier from this point- when you click on one of the workouts in the tile list, it brings you to another page to display the workout in more detail.
From this point you can actually use the dropdowns on the left to look through other collections of workouts, plans, and custom workouts.
… at least for cycling. It’s probably pretty close for running, I assume. 
This Season on Zwift: a Refreshed Workout Library UI | Zwift Insider is where I got most of these pictures. Zwift Insider is your source for all good Zwift things.
whatsonzwift.com is a good place to search the workout library
Scheduling workouts I believe would require a third party app like TrainingPeaks
Thank you very much. The point for me is I want to be able to start a workout right away …say the next day. So when I setup Zwift and get ready to run I go right to the workout I picked out the previous day and start it. No searching while I’m standing on the treadmill …lol
There really should be an online website way to manage workouts etc.
I want to search for training and workout options and add them to either a calendar or better yet a “My Favorites” that I can quickly choose from when just getting the app fired up and mounting my bike.
The queueing feature supposedly coming soon to the Companion app might help with this. We haven’t seen the feature yet so it’s hard to say how useful it will be, but it’s worth checking out once released.