Joining a target school abroad in 2023-24 session, currently on a gap year, need some advice

Indian here going to a target school in Europe (Bocconi) for my undergraduate course. I have a B1 in Italian which I ill try to convert into a C1 by the time I join my bachelors program. Although I do want to enjoy my gap and have fun, I also want to utilize this time to add something genuinely impressive on my CV. Currently I only have 2 mediocre non-finance work experiences. One is me being a personal trainer and an online coach for the past year or so and another is my experience at a local luxury retail and manufacturing startup as a part time sales associate.

Since it is already fucking hard to break into IB/MC as a local even after coming from a target school, breaking in being an immigrant would be significantly harder, So I need to plan ahead and build my resume up relatively early. I do plan on pursuing a masters in Europe/UK (St Gallen, Rotterdam, HEC, ESSEC, WHU, SSE, UCL, Imperial, LSE, Oxbridge, Warwick etc.) but having a free ass year and not doing anything that reaps me dividends in my career just seems like a fancy version of procrastination. I have genuinely set my mind into breaking in, MBB being a high watermark target.

I am thinking of doing independent research, or trying to go full time and rise up the ranks in the luxury startup I am working at. If you guys were in my place, having the hindsight that you need your resume to be impressive enough for the big firms, while being an immigrant student, considering currently I cannot study and increase the other main factor of my resume, ie, my GPA (I hope I am smart enough to be in a top percentile at my university), what would you do? Any and all advices are welcome, thank you for reading.