A lot of us have trouble even sticking to things we are interested in. It seems like some symptoms lessen or go away as we get older, but many others either stick around or get worse. I had some mild hyperactivity as a kid but now I'm too fatigued to concentrate even on things that interest me a lot of the time, regardless of sleep and eating patterns (which I'm very careful about). My working memory has almost completely left me as I've gotten older (I'm late 30s). That one affects me in everything I do unless I'm hyperfocusing on something pointless. Hyperfocus is fun but you lose track of time. You'll need timers and methods to keep track of your productivity.

Also, I don't know how your social life is now but you will have less and less opportunities to make friends and meet people as you get older, so you better make sure you stay in people's good books and don't forget to contact them regularly. You need those contacts and connections to support you when job hunting. (It's not just about having the qualifications and liking the job. That's just a basic prerequisite. You also have to beat out everybody else who is trying to get that job, too, unless you have the money to fund your own business. If you have that kind of money, then you can do whatever you want. Money isn't happiness but it is freedom in this world.)

People with ADHD have a tendency to be in denial about the effect our symptoms have on our ability to thrive. I have seen both for myself (despite doing well in grade school and graduating university) and others what kind of damage that can do and I wouldn't wish it on anyone else.