Though i am not a day trader but i could definitely recommend to you Binance. Liquidity, low transaction fees at secured gamitin yong platform nila. Maari kang pumili sa napakaraming exchanges ngayon but with my experience in scalping, trading masasabi ko na maganda ang Binance pero ingat ka rin sa ganitong larangat kasi napaka delikado, pweding mawala ang pera mo sa isang iglap kung mamalasin ka. Better if you join some telegram groups that solely discuss trading, marami diyan.