You are such an impatient person. In such a hurry! I say it as if it's unexpected, but of course you are. Look around you. You're in a society that celebrates youth and the overnight success. It's a real-time world built for short-term gains and instant gratification. Meanwhile the daily parade on social media makes it easier and easier to compare yourself with others, and harder and harder to find contentment in what you see.
I know it makes you unhappy. I found this passage you wrote in your journal, at the times it was getting to you most.
"I am struggling under this weight of not knowing what to do next. All the while my twenties are slipping away. EVERY DAY I COME UP WITH NOTHING AND I HATE IT."
Capital letters. You never write capital letters.
So here's something you learn a short ways down the road: things that matter take time. More than that, the only things you should do are the things that matter, and they will take time.
So, take a deep breath, and be patient.
You'll find peace with this eventually. You'll see there's a long game to play, and where you are tomorrow, compared to yesterday, means nothing in the long game. You'll realise that you won't achieve the success you seek until you're forty, or maybe older. In the meantime others will appear to race past you in life - but that's a parallax illusion: they're on a different level, they're not playing your game.
Here's one more thing that you should have figured out earlier.
On a cold winter's day in the future, just before it's too late, you'll move to Paris with very little warning. (I won't tell you when, that will spoil the surprise). You won't be able to speak french, you won't have a job lined up, much money in the bank, or even an apartment. But you'll do it anyway.
Strangely, this will amaze most people, especially the ones who know you best, and they'll ask: 'how did you do it?' 'Surely' they'll say 'you must have known some french?'
The answer to those questions is something that will stick with you for a long time. In some ways it's the secret sauce to it all. How do you do it? You have embarrassing encounters in boulangeries. You spend most of your time looking stupid and bewildered. You make compromises, bad decisions and last minute mistakes; in other words you muddle through.
It fills in the gap that the "just do it" evangelists leave out when they say 'leap and the net will appear'. It will appear, but you'll have to tumble through bushes, down sharp inclines and over rocky ledges before it does.
That's all you have to do. Start. Make lots of mistakes. Repeat.
Do I wish I could really go back in time to tell you these things and give you a head start on yourself? I don't know. Advice is meaningless unless you're in the right place in your life to take it. Both of these realisations came in their own good time and were hard won. That's what makes them matter.