I'm very sorry your male budgie didn't make it...
Unfortunately, from these photos it was clear that he was struggling with an illness.
Be sure to wash and disinfect the whole cage and accessories and have your female budgie examined by an avian vet or a vet experienced with birds.
Given the current circumstances, now is not the best time to think of getting another budgie, not when you don't yet know if the illness that took your blue boy was passed to your female budgie.
Check this website, it seems this clinic on your area has avian services: https://www.indiamart.com/supreet-veterinary-clinic/
Here is a list of Veterinary hospitals, you can see some offer services for exotics pets where budgies are included.
Cover the cage on 3 sides in order to keep her warm and more comfortable.
If you have millet spray, you can soak it in electrolyte solution in hopes of giving your budgie a little boost and encourage her appetite.
For detailed info, check this link: https://talkbudgies.com/your-budgies-...te-recipe.html
You can also offer egg food to your budgie as this is highly nutritious.
In case you don't know, any new bird must be quarantined in a different cage and room as a preventative measure in order to ensure any potential illness carried is not passed to the current pet bird(s) you already have.
Take a few months' time to truly connect and get to know your budgie's personality so that you have a better idea and are able to make a more educated decision on what is best for her overall happiness and welfare.
Depending on your budgie's personality and the general receptiveness she has towards you, on the amount of daily quality time you are able to give her and the work in taming that you put into her, she can be perfectly content and happy by being a solo budgie.
Best of luck with everything.