Concrete wall drill bits

In your case it isn't so much a matter of the drill bit as the drill and drill bit combination.

An SDS drill is what you want with obviously SDS drills. That will fly through concrete and make good round holes.

The next best option is an percussion/impact drill (not to be confused with an impact driver) which has a "hammer" action. With that you use tungsten carbide tipped drill bits. If this will do the job and often it won't it sometimes takes so long at it bashing away that the hole is enlarged so the raw plugs won't fit properly.

Even for very occasional DIY use its well worth getting a cheap SDS drill and a few bits for it because it really does the job.

If you don't have a drill with a hammer action of some sort you won't get very far.

Something like this is what you need https://www.amazon.co.uk/Einhell-RT-RH-Rotary-Hammer-Drill/dp/B00YMJ4K9M/ but you can pay more for a bigger brand name if you want. Bits? - these will cover most needs https://www.amazon.co.uk/Bosch-Piece-SDS-Plus-Drill/dp/B001L1RAY6/ but you might want a 10mm bit for hanging say a TV.

As above (great advice) - SDS drill makes short work of concrete... it's more about he drill than the bits. However - the "hammer" action setting you see on most drill/screwdriver combo will drill 5 or 6mm holes, 30/40mm deep for small jobs.

Just be aware that there are 3 "bit" types (wood/metal/concrete), on the standard bits. The SDS bits have a shank with grooves where it attaches to the drill.

LIDL have a range of stuff in store from tomorrow. https://www.lidl.ie/c/weekend-sale/c778

Might be worth a punt at the price?

Just to add...

The plugs and screws that come (free) for fixing with most things are pure CRAP!

Get off to screwfix and get yourself some decent plugs and screws for your tool box!

Get a decent mid range SDS drill and a set of SDS bits to go with it. You won't regret the extra few bob and it should last the rest of your DIY life.

Even a cheap lidl sds is miles better that a non sds hammer action, I'd say any new house owner who is planning on doing a bit of diy should pick one up. Might be worth picking up a decent drill bit. Realistically for diy jobs you are probably only looking at 1 drill bit size and the matching rawl plug size you don't need a whole range of sizes.

Surely you shouldn't be drilling into concrete lintels? Potential to weaken them substantially if you hit the steel.

Also, I have both and there's no need for an SDS drill for oddjobs about the house. A standard cordless with a hammer action more than suffices.

These Irwin concrete drill bits are the business (non SDS type):

They would go through a tank (if a tank was made of concrete of course)

You can get an SDS drill the will go through it (I have ones that will drill through rebar) but I don't really recommend it. Next option is to put a strip of wood across the top of the window and screw that in where can paint it (or before putting it up) then you just use wood screws.