Assume that the future can change based on your actions, so any historical information that you bring along with you from the intervening 25 years may quickly drift out of the new realities history.
Edit: also assume that you can be given a healthy 21-year-old body if you want or take your previous self’s place.
Further, identification will be provided for you if you were not born at that time.
So prevent it from happening!
One of the reasons why the coronavirus vaccine was created so quickly was that the work was already 90% done.
If you orchestrated things that you would be a billionaire by the 2010s, you could purchase the company that designed the vaccine and make sure that they are appropriately funded so that the vaccine for coronavirus would already exist at the time the pandemic struck.
And billionaires didn’t have to isolate in a studio apartment.