Having slight to severe dizziness with legs feeling weak at times. This feeling is everyday almost around the clock. What could be the reason?

Many reasons. Could be ear, heart, or metabolic cause. See your doctor.
Evaluation needed. There are some things to be concerned about such as anemia, low blood count which can cause light headedness or weakness. Heart rhythm abnormalities are a concern such as a rapid or very low heart rate. There also could be vertigo where the room feels like it is spinning. There may be a concern for dehydration if you have been working in the heat. Visit a local primary care doctor to be assessed.