Some good advice on here.
Also, take heart, it feels harder right now because it is harder. People's experiences from 2,3,7,8 years ago are far less relevant right now.
Fewer employers are hiring, particularly at entry level and the rising use of AI in recruitment means having a real conversation with a real person is for those that get through to round 4...
There are very few truly young people staffing the cafes, shops, pubs on our local London high street, even at weekends. They look to be permanent older staff.
Of those I know who have combined studying with a bit of work, its mostly been during school/college holidays rather than weekends and has been temp (zero hours) roles with agencies for shifts like waitressing at events etc. So no guaranteed income and little notice of shifts. Unless you're in an area where people really do put cards in windows or welcome a personal visit and a chat, agencies might be your best bet.
And rural areas can be particularly hard, relying on cars/drivers. I know one tourist area where the temp staff are mostly non local students from affluent families - and are paying rent to stay the Summer and work in the remote coastal location. Many locals can neither afford/justify that rent or manage the daily practicalities/cost of another car/driver in an area with little public transport.