Sadly I suspect this is worse than it looks at first glance.
Ouch that's a really messy repair. A body shop would give the best results but is likely to be expensive, DIY will be very labour intensive and probably have poor results.
That.
Any paint job is only as good as the preparation, and in this case, the preparation is of very poor quality. If you want a better finish, the preparation will have to be done again.
As others have said, this is going to need sanding back to sound materials, more body filler, more sanding, then a complete paint system; primer + topcoat + lacquer, blending it into the adjacent panel(s).
To get a result that isn't going to look like an obvious repair, the bumper will have to come off; refinishing the bumper may need different materials and paint to refinishing the steel panel.
You could certainly improve on this result at home, but getting it pristine isn't really a beginner's project. It's way beyond needing just a quick rub down and a rattle can. A proper professional repair will likely cost multiple hundreds of pounds; you'll easily spend three figures on materials even to DIY it. Decent quality paint isn't cheap, and poor quality paint won't give you a lasting finish.
Also be prepared to find it is significantly more damaged than it appears once you start working on it.
If I'd seen this on a car I had been contemplating buying, I'd have walked away, whatever the price.