Just playing poker can help you get familiar with the poker environment and allow you to practice certain skills (like learning math odds), but they won't teach you anything worthwhile that poker books, mentors or just experience can provide. Even just by watching the game of a strong regular, you can learn a lot, look at different game situations and decide for yourself what is best for you. At first, you can get into a series of failures, but if you work on your game, on your skills and strategies, you can get good results. If there is an opportunity and a desire to play poker and develop, then training is a must.