I feel weakness

How to treat your condition ?
Treatment depends on identifying the cause, and in cases of anemia, iron pills and vitamin B12 pills should be taken, and in vitamin D deficiency, vitamin D supplements should be taken. You shpuld have a healthy diet rich in vitamins, proteins and minerals, eating nuts and Seafood. Exercising continuously, exposure to sunlight. Ensuring adequate intake of water during the day at a rate of 2-3 liters per day
What medical investigations are needed?
You shuold undergo a medical and clinical examination by the doctor, do several tests including a complete blood test CBC to check the level of hemoglobin in the blood, check the level of iron and vitamin B12 levels, check the level of vitamin D, analysis of thyroid hormones TSH, examination of blood sugar to exclude diabetes,  electrocardiogram ECG for the heart, and a psychiatric evaluation may be given
What are the causes of weakness?
There are many reasons that cause laziness and lethargy in the body, the most important of which are the following
Anemia
 Diabetes mellitis
Low blood sugar
Heart diseases
Deficiency of some vitamins such as vitamin D and vitamin B12
Pregnancy
Infection, infection, influenza, and cold
Thyroid disorders
Malnutrition
Lack of sleep
Stress and anxiety
Depression
 advice?
Follow the previous advice and follow up with the specialist