Hi and welcome
Please please please don't do VLCD - please. Most people who do lighter life or cambridge diet, etc. put the weight back on after and more besides and compromise their health. I know there are exceptions - aren't there always? You want to lose weight for health reasons...then do it healthily.
There is so much great advice here - read it all and you will see you can lose weight without resorting to VLCD. I know what it's like to not be able to walk - I badly broke my ankle last Summer, have screws and plates in and have pretty much been told to expect arthiritus in it at some point. This is one of my motivators for losing weight - After over 6 weeks of not being able to walk and months or learning how to walk normally I am terrified of not being able to walk in later life. My auntie is very overweight and at the moment can barely walk.
You've been given 10 years to lose weight - you can lose that amount in 10 years easily with a lot of hard work. I'm an all or nothing person but the most important thing I learnt about weight loss is there are no short cuts and no easy ways out - it's hard work all the way. I'm fortunate I'm losing weight fairly quickly at the moment (1-2lb per week), I'm dealing with any of my issues with food. Why do a VLCD and risk putting all the weight back on or risk other health issues? I calorie count and it's working well for me and means I've had to learn to control eating better. Have a good read at all the information on the stickies here and look at the before and after photos people have posed and see it can be done. I'm 5 stone down from the weigh I was just over a year ago - I seriously never thought it possible for me but it really was and it is for you too.
Good luck with your weight loss journey whatever you decide.