Rowing is great for legs, back, and shoulders as well as biceps and obliques. However that’s only about half of the muscle groups you have. It will also be great for cardio but if you want a total body workout, the best thing to do is train all of your muscles. If by skinny you mean you are a hardgainer or someone who has trouble adding weight to their frame, the best way for you to put on weight is to eat a lot of good food and train heavy. You are not going to put on a lot of weight if you do a lot of cardio with low resistance. You need heavy weight and about twice the calories your body needs or more. And skip cardio for a month at a time to help you pack on the lbs. You can always run every other month for good cardiovascular health, which is important, but cardio everyday will cut your gains considerably.

take a walk with weights in hand ,,,

Not by itself. Honestly, neither will a home gym, unless by “home gym” you mean turning your entire garage into a gym like a power lifter.