Its a letter box cover Bob.
Box for collecting post on the back of the front door. The photo is at 90 deg. If you click it it's more obvious. How hot is it over there ATM?!? :shock:
I'd echo what StanleyMonkey said.
You have to sort those screw heads out unless you need access? I'm guessing you're not planning on unscrewing the top each day?!?
Not sure what tools you have but if you are brand new to any tools and have a bare minimum and have driven them in by hand with no drill and can't get them in any further, you can pick up old stanley hand drills cheap at all sorts of places. On ebay there are several going for a few quid.
https://www.ebay.co.uk/bhp/stanley-hand-drill Boot sales can be even cheaper.
There are lots of makes and so on but this will get you started and never run out of battery... Good quality tools, buy the old Stanley ones not modern new ones. Don't ask.
Get a countersink bit. The first one in the link below. This will let you drop the screw head below the surface
https://www.ebay.co.uk/itm/3pc-1-4-8mm- ... SwnBZbf6j0
You're off for less than a tenner with two tools you can use for life.
You can punch the nail heads in with an upside down nail and hammer if needed to start out.
One good tip here is that some fillers and non oil based paints won't stick to metal. So it's worth buying a small dirt cheap tin of gloss. A sample from a paint shop or Homebase etc. If you don't have an old half empty tin lying about a good source is Humbrol model paints if you want a small amount new at low cost. Tiny tins. Varnish will do if you have a bit spare.
For filler, if it's on the back of the door (hard to see) that's going to see a bit of dynamic stress and impact I'd use a two part filler. If it's on a wall pollyfilla powder type will be fine and a lot easier to mix and apply. (Add the powder to the water :wink: ).
The only finish for this is paint to be honest. Any type of stain or varnish is not going to work. That's fine, it will look great for a first project IF you take the time and care to address the issues in the preparation stages. If you tosh a bit of paint on now and you're happy with the result good luck too. It's your house, your approach but I bet you won't be doing this in 2 years as a hobby if that's your inclination.
Your choice on the paint finish. A matt finish will gently quieten any production flaws, a gloss will be harder wearing but unforgiving.
Well done Tesh. Good start mate. =D>
Good stuff.
Cheers,
Chris