Not to bash drinking, but I find it has loads of knock on effects - like you, my sleep goes to pot if I've been drinking, lack of sleep makes me want to do less, and in general creates negative feelings. Sleeping well, waking up refreshed (ish - I'm not a morning person 😂), makes facing the day's tasks ahead much easier.
Also, I've got more into my exercise as I've got older, and drinking makes that harder and I'm much less bothered to do it if tired and/or hungover.
Paradoxically, doing more exercise gives me more energy, so I tend to get more done overall, plus, rather cheesily, it gives me me a sense of being able to achieve more. I'm not one of life's naturally sporty people, I don't naturally gravitate to it, but I can see its benefits, and that (along with an insistent Apple Watch and a DH who IS naturally sporty) keeps me going. I can't have too long 'off' or it's too hard to get back into it.
Good luck, if you want it, you can do it.
My other piece of advice is to have the changes you want to make SMART - specific, measurable, achievable, relevant, and timetabled. So instead of saying 'don't be lazy', try, 'I'm going to do 30 mins of exercise every M, W, F at 6pm before dinner (or while it's cooking)'. If you can see the end goal and the pathway of getting there, it's much easier and achievable than a blanket, I must be better.