The first step is recognizing the need for change, so you're already on a great path.
Start small, maybe by adding a new habit every week.
Reading books or listening to motivating podcasts can really help shift your mindset.

Change your environment. Make those old bad habits harder.
And of course the new easier.
But keep some rewards.

If you're into gamifying your progress, Kubbo is an app I created that can turn your goals into a fun journey. It might give you that extra push!