It's possible to "play" VTD any time. Once get the process of getting into VTD through one of the programs, can just navigate through rooms, do attacks, cast spells, adjust HP when you "take damage", etc. Won't be connected to any particular dungeon or to the DM side stuff, but it's really helpful and really easy to practice navigation before actually playing.
I know how to do it, so it took me about 2 minutes to spin up an instance using tdcharactercreator.com and start doing spells in room 1 using a pregenerated Wizard. Obviously, it's going to take some getting used to the UI, but it's really actually quite easy to get into the environment to test stuff out. When doing an actual run, need to do a couple extra steps to put in difficulty code and code to link to a specific run, but there's plenty of time to go over that before you start playing with the 24+12 minutes for coaching and training before room 1.
I think it's fine to try VTD first, but it's a different experience, so whether you like it or not largely tells you whether you like VTD or not and doesn't really indicate whether you will like in person play or not.