If you are just starting out, and you are looking for ways that you can work out from home, there are a couple of important factors to consider before you begin a life of home fitness.
What is your age?
If you are between 16 and 30 years of age you will probably be able to perform any type of exercise at a high level within a couple of weeks. The reason for this is your body is still young and flexible enough to adapt to what you may put it through. This does not mean that you should perform exercises without proper form, and you should carry out dynamic stretching before starting, and static stretching afterwards.
If you are over 30 years of age, you will want to ensure that you start out slowly, because there is more of a chance of injury that could disable you before you even get a chance to get started. Basically, you should give yourself at least 3 weeks before attempting to perform intense exercise. Also, warm up and or dynamic stretching is important for this age group to help avoid injury.
Do you have any medical issues?
No matter what your age, if you have had any medical injuries or have not been able to perform simple exercise such as walking, you should consult your physician before attempting any exercise program.
Any medical issue that has to do with your heart should be taken very serious before starting exercise. There are certain types of strength training exercises performed above your head that should be avoided. Once again, if you are unsure of any type of medical issue that may be a factor before you start any exercise program, consult with your physician.
What are your goals?
Setting specific goals will enable you to focus on exercising in a precise way that will help you to obtain those goals. In other words, a specific goal is not "I want to get into shape", because this is far too general. For example, if you do not get much cardio activity you may want to improve on your long term cardio endurance, or you may want to improve on your short burst cardio endurance. Let's say you have decent cardio but you want to improve your strength. Now, this again could mean that you want to improve your strength endurance, or it could mean that you want to improve your short burst strength. You may also only want to 'tone' up your muscles, or you may want to really bulk up. So goal setting is an important first step.
Ready for Action!!
As a beginner you should only exercise every other day, while trying to avoid using the same muscle groups back to back. For the strength exercises that involve lifting or pulling weight, you should only use enough weight so that you can perform at least 10 - 12 repetitions, and keep your sets to around 2 or 3 (meaning 2 or 3 sets of 10 - 12 repetitions).
Simply use your common sense when approaching any workouts from home. What I mean by this is start off gradually; don't be in a rush to exert yourself until such time that you feel as though you can perform an exercise without injury. If you are just trying an exercise for the first time, take it slow and see how you feel the next day. I have seen many situations where people push themselves too hard the first time, and pay for it dearly the next day when they can't get out or bed. Basically, listen to your body and remember that you have a lifetime of exercise still in store, so there is no rush to the finish line.
In conclusion, there is no exact answer for how much or how little to carry out when doing workouts from home, because we are all individuals that have different fitness goals, different body types, and are at various fitness levels. In addition, all individuals recover at a different pace depending on age, fitness level, and genetic makeup. What I describe in the paragraph above as far as time, repetitions, and sets, are only GUIDELINES. If you take your time, and try numerous different exercises at many different speeds and weight, keeping in mind what your fitness level and goals are, you will find a workout from home program that is tailor made for YOU.