On antibiotics amoxicillin need to do complete regular bloodtests can i do them or how long do i wait for antibiotics to leave system if so?

All depends on what: you are looking for. Antibiotics (against-life-things, i.e. poisons to micro-organisms which most humans tolerate well) do not alter most blood test values. However, values resulting from infection: blood cultures, white blood cell concentrations, or specific antibody concentrations related to infection (beyond current clinical tests) would change if reflect antibiotic relevant infection change.