我要上班-- 1、 I will go to work. 一会儿我要上班。（I will go to work later) 2、 I want to go to work. 我待在家里的时间够长了，我要上班。 （I stay at home too long enough, I want to go to work. 3、I have to go to work. 今天我要上班，不能和你出去了。（I have to go to work today, can not hang out with you.) 我得上班-- I must (have to) go to work. 不能再待下去了，我得上班了。（Can't stay any longer, I must go to work.) "得" is stronger than "要" in this case. Hope can help you :)

我要上班 - I will go to work 我得上班 - I have to (must) go to work

我要上班: 有主动的意思，此处的“要”有要求(demand)的意思，我自己要求上班。 我得上班:必须上班的意思，可能是自己要求自己上班，也可能是别人要求自己上班。