I can think of few things that you can start doing right away, that can help you transform/improve in 30 days.
Ensure that you go for a walk / work out for atleast 20 minutes each day. You can build it up to 30 or 45 or even 60 minutes slowly. Plan that you get a workout, atleast 3 to 4 days a week.
2. Always watch what you are eating. Try to cut out sodas and junk food as much as possible. It can help you stay fitter.
3. Reduce time on your smart phone. Have 1 or 2 hours every day or a fixed time when you will switch off data and spend time outside, with real people and friends. Life is outside.
4. Pick up a new hobby - what ever it may be. Reading, learning to play an instrument, try something new. It will help you meet new people, and learning something new is always fun.
5. Plan your day better. Identify which time of the day you are most productive, and ensure that you complete the toughest work at the most productive time. That way, you can put out your best work.
Try these and tell me in a month as to how you feel.
Best of luck to you.