Meditation is the art, science and practice of directing your thoughts. You practice meditation to control your thoughts, the response is a calm mind and body. Thereby achieving not only a measure of peace and tranquility, but the ability to find focus and clarity in stressful situations even when you are not meditating.
Calmly meditating also has the wonderful benefit of lowering your heart rate, respiration and your blood pressure. The benefits are immediate, good for your body and your mind as well.
You do not need special pillow, clothes, various accessories or even a special room to get started. This makes it very affordable.
Contrary to some advice you may have received, you do not have to sit in the lotus position or any other specific pose in order to meditate successfully. It's a real concentration breaker when you develop a cramp or your butt begins to ache from sitting on a hard floor! So a pillow, a folded up blanket or even borrowing a cushion from the couch or chair will suffice for something to sit on.
You can even sit in a chair if you prefer. Just sit however makes you comfortable, but remember that it is crucial your spine is straight to conduct the energy efficiently and to transmit the breath.
Breathing "right" plays a tremendous role in meditation and especially for beginners. If you learn a bad habit now, it is much harder to break that habit later. There are myriad breathing techniques, but if you can just focus in and follow your natural cadence, you are off to a great start. Do what works for you and don't overcomplicate it.
Someone can guide you in meditation but no one can actually "teach" you how to meditate. It is a self-discipline that you alone are responsible for mastering.
You can seek advice from many sources, but in the end, it is up to you. If you are completely new to meditating, a good start is just to focus on slow, steady, relaxed breathing. Observe it going in and out without trying to control it. Focusing on one thing is a step closer to focusing on nothing, which is the ultimate goal.
Observe how you feel when you are finished. Each time, try to increase how long you sit.
In this way, you can slowly and successfully improve. It does take time. Be patient and be proud of each attempt. Over time you will have established a new relationship to your inner world and then you can experiment from there. Good luck.