Is it possible to start working while studying abroad, like through OPT or CPT in UK?

Yes, you can work while studying abroad, but the rules depend on your country and visa type.

In the UK, full-time students on a Student visa can work up to 20 hours per week during term time and full-time during official vacations. Some work types, like self-employment or running a business, are not allowed.

In the US, F-1 visa students can:
- Work up to 20 hours/week on campus during academic sessions
- Use Curricular Practical Training (CPT) for off-campus work related to your field during your studies
- Apply for Optional Practical Training (OPT) to work in your field after graduation (typically up to 12 months; STEM graduates may get an extra 24 months)

Visa rules and work opportunities are subject to change.