Allowed external access to a spreadsheet for multiple users but locking visibility

Hi all,

I'm hoping you can assist. I used this forum and the great minds to help me create a few formulas I struggled on when creating a spreadsheet for a fitness club I run. This club "scores" individuals based on certain criteria each week, and displays that so I can then snapshot each individual's results, and send it to them (currently individually, on WhatsApp).

I am looking into websites and more bespoke development around the data capture and delivery however I was wondering whether there might be something I can do in the interim to achieve my desired outcome.

Essentially each row is an individual, and each column is a unit of data captured against them (weight, BMI, goals scored, targets reached, current weight, variance from previous week, etc). What I'd love to do is find a way of sharing this spreadsheet, but locking down visibility of the row data only to the individual it corresponds with. Currently I know I can do this en masse, but it needs to be dynamic based on the user that logs on to access the spreadsheet.

Any ideas? (sample attached not that you really need it - more conceptual question)