Exercise is vital, it is a big part of a healthy lifestyle alongside a good diet, and good sleep. I'm sure everyone wonders at some point how often should they exercise, and sincerely there is not an answer for everyone, everyone is different but that doesn't mean that I can't help you. Effective workouts routines contain three parts, number one being to focus specifically on one type of workout or body part (fat burn, HIIT, upper body, legs, abs, etc), with the intention that you cover the entire body by the end of the week, the second one is having rest days, because you need to give your muscles time to recover, and the las one and I think its the most important is to have good sleeping routine, sleeping not only helps recover your muscles, burn calories but it helps you overall to stay focused, energetic and in a good mood throughout the day. My recommendation is to workout 4-5 times a week as it gives your muscles 2-3 resting days, and is enough time to train the whole body. Remember, everyone is different and you shouldn't exceed yourself to get to a certain level, with patience and perseverance you will get there. Always train safe and don't do an exercise if you don't feel ready. Good nutrition is key, try to keep your sugar low, about 40g of protein per day, and eat some carbs, they give you lots of energy. Have a great day.