I suggest creating two characters first: the 'past life,' and the present, pre-powers self. Then decide with the GM how much from the past life should be transferred to your modern self
now, and what you'll work up to over time (and whether you'll go in a different direction than your 'past life' did). Depending on the game, you might start out with only vague memories of the past, or with complete detail, or anything in-between. Your past life should be something your present self is compatible with, which is to say that they should have similar personalities, and at least not wildly different body-types (a character who is transgender or otherkin might have a past life with a body-type that better matches their mind than their current body does, though). That doesn't mean that they should have the same personality in both bodies, though, just that they should be similar enough that you could believe that each was a version of the other. Likewise, one could be a villain in the past and a hero in the present, or vice versa.
You can choose to have an older character who was an adult or older child in 1950, with memories that partly match the past that they remembered before people started Reawakening, just with strange abilities and adventures added (Reawakened folk who were children or teens at the time would most likely remember being kid sidekicks, possibly to someone who is now much younger). The younger the character was in 1950, though, the more it makes sense for them to instead have the memories of some other powered person, who died before they were born. I recommend that older modern characters (anyone much over fifty at campaign start, in this context) have abilities that improve their health and restore to some degree attributes and abilities lost to aging, but that's not an absolute requirement.
Depending on the GM and the players, the past life might be an original character, or your adaptation of a character written by someone else (since you're presumably not trying to make a profit off of it). In case it matters to you, here's a wiki of
Public Domain Super Heroes.
The Free Universe is similar, but not a wiki. You might also find the
Wold Newton Universe a useful resource, along with
some related websites (that's just a sample, there are a number of others).
Pointwise, these Golden Age supers tend to be 250-point characters or higher, with sidekicks mostly being in the 100 to 200 point range (though some sidekicks were rather more powerful than that, sometimes beyond even the 'main' hero). Generally, I suggest that 500 point supers are uncommon, 1,000 point characters are rare, and 2,000+ point characters are
very rare. Not all of them are human, as animals, aliens, robots, plant elementals, and other such beings have been seen.
Most active supers (and some who don't get out that much) will tend to have some form of Injury Tolerance (usually Damage Reduction), Damage Resistance, Enhanced Defences, Hard to Kill/Subdue, and/or some other means of not dying and not getting seriously wounded when people are shooting at you. 'Piercing Only' and 'Ranged Only' are reasonably common limitations to DR and IT: DR, though they tend to be on top of a less powerful variant that is less limited (because you can take a punch pretty well, too). Rapid Healing and Regeneration are also fairly common, and Luck-related advantages are very common. Even 'Super Normal' mystery men will tend to have these (generally under 'Savant' or 'Cinematic').