Hello @zen.fit and very nice to meet you. There is lots of articles about this topic and I can attach couple links from some most reputable sources for you to read up on everything you need to know while making this transition.

This first article can give you the basic answers to your questions: Is Being Vegan Healthy? Here’s What The Top Nutritional Organizations Say

Besides, I would also suggest to contact Katie, @plantstoplanks, who is vegan and a personal trainer and knows great deal about nutrition in connection with fitness.

Dr. Greger's M.D website Nutritional Facts has practically everything covered, although it may not be in one article.

I hope this will be helpful to you and please let me know if there is anything else you need to know.

Wish you all the best,
Lena