OP, if you want to have a good first horse buying experience, then you need to get a good horse. I'm not saying that there's anything wrong with the filly, she just wouldn't be a good fit for you. You have limited experience and she would need a confident, knowledgeable handler to do her justice and give her some chance at a productive life.
In most areas here in the states, you can buy a gentle, decently broke (no vices, just doesn't know much past kick to go and pull to turn and stop), for a pittance.
Just consider this. You can take this filly for free now, spend at least a year and a half worth of feed, farrier, vet bills, plus trainer bills when it comes time to get her broke to ride (which is at least a year down the road) before you can ride her. Even after all that, she would still need a confident rider because she would still be very green. That would add up to thousands and thousands of dollars. Or, you could spend, at most, $2500-$3000 now and get a super nice, super well trained, push button horse that would guarantee you a pleasant re-riding experience and give you confidence.
Buying a horse that's right for you.