・・・、。
...Alright, shall I throw myself into my studies again today?
Literal
...Well, today also studies [to-に] throw-myself-[volitional-しもうか].
勤しむ (いそしむ) is a literary verb for 'to devote oneself to, apply oneself diligently to' — formal and slightly old-fashioned. The volitional ~しもうか at the end is the self-directed 'shall I?' form, used when the speaker is psyching themselves up. The overall register is mildly self-consciously elevated, as if the speaker is making a light show of resolve. さあ at the start is an attention-resetting 'alright then' or 'well now'.