Do you think I could lose a noticeable amount of weight by 9th June?

you could lose 20 pounds by than

I was hospitalised in 2016 & had to be put in an induced coma for 5 days & on a machine controlling my breathing for 5 more. I was "fed" some sort of liquid stuff through a line. I lost about 9-10 kg (20-22 lbs.) in that time. I was so hungry that my stomach ached constantly. So yes, it can be done.

I don't know you o how much overweight you are. People who are significantly overweight can lose a noticeable amount (10 pounds+) in a month, but most people should look to sloe 1-2 pounds a week.

When trying to lose weight and get healthy, it is a really bad idea to set unrealistic goals that only make you feel like a failure. Instead, focus on following whatever healthy diet/lifestyle eating plan, you've selecting and doing daily exercise. Whether or lose 5 pounds or 25 pounds isn't as important as improving your health and continuing on the journey to a healthy weight.