If you are doing it, do it for you, not anyone else but I can fully see where you are coming from.
You can definitely lose a significant amount of weight in 10 weeks, it's all about calorie deficit, but making good food choices with your calorie allowance. Moving more will help too if you can up your step count.
In terms of glowing up absolutely, but its a case of money, time for appointments and routine.
I think starting from the foundations upwards is the best way, start with your canvas if you will. Skincare first. Get a cleanser, toner and moisturiser - doesn't need to be fancy, use dermatica or skin+me to get tretinoin on prescription - this will give you a glow and reduce wrinkles. Get a serum with hylauronic acid, and an SPF50 cream. Also if you can take supplements, I use viviscal but I hear Asdas multivitamin is excellent too.
Eyebrows, microbladed or powder brows, around £300-£400 but perfect brows. Also I think a last lift and tint helps, or if like me your eyelashes are sparse, lash extensions.
Nails, even just a gel helps polish off the look.
Spray tan a few days before the event, or do at home, I use vita liberata which is very natural, not ornage at all.
Teeth whitening, expensive but needs to be through a dentist, see what your dentist offers. Enlighten(?) is around £500, my previous dentist does Phillips Zoom which is closer to £200. Failing that, even a hygeniest clean will give your smile a boost.
Hair, use phillip kingsley elasticiser or olaplex, people tend to get on with one or the other, I have fine hair and only get on with phillip kingsley elasticiser. I also use a jkeratin straight treatment (brazillian blowdry the hairdressers call it) costs around £26 on amazon and does the same, gets rid of frizz and leaves the hair smoother and shinier. A balayage can give hair a boost.
Makeup I guess would be key too, go to a MAC counter or any other high quality makeup brand and explain what you want, and they can talk you through the steps.