Spend money on your health.

Do you play sport ? Buy stuff for that sport (shoes, ball, bat, ...)

If you live somewhere wet, get a good quality waterproof coat. Like actually waterproof, not these fashion coats that really aren't. £100-200/but it'll last you at least 10 years. Assuming you're at the end of teenagerhood where you've finished growing.

Otherwise I'd save to get a hifi system of decent quality. Something like wharfedale diamond 9.1 speakers and a second hand NAD amp, 3.5mm to RCA cable. Would set you up for a long time of musical enjoyment.

My best black Friday was spent with a good friend going around the city, getting some food and something momentous and something for my hobby.

I still have the blanket which reminds me of the day.

As others have already said, chances are there's nothing you genuinely "need" for BF if you are asking here. However, that doesn't mean a nice experience is impossible.

oh I might be able to help you.. with a song about thrift! when you get a penny from a chum, don't just spend it on bubblegum. Put in your cap, put it in your cap

https://youtu.be/icfzrBm-vuU?si=dUz9syGoF_v9vBSL