Hi @SarahK1996,
That's an awesome 30th gift, I'm sure your partner is stoked.
I can't feel the benchtop, so I can't really say for sure what it is, but the top does look like it could be engineered stone, in which case you would use a diamond bit such as this 10mm Diamond Core Bit to drill through it. You can use this bit with a standard drill, but you're going to want to ensure it is not in hammer mode, as the percussive action can cause the material to crack.
You're also going to want to wear a p2 rated mask or higher, as silica dust can be released into the air, and you absolutely do not want to breathe it in, as well as eye and hearing protection.
Take it slow to begin with, as it can slip on the surface before biting in, and make sure you wet the surface while drilling, as this will help to keep the drill bit cool as well as reduce airborne dust. You want to drill down through the surface as if you drill up, then the visible face of the benchtop could potentially blow out, which is not ideal.
If the engineered stone is sitting on an MDF or chipboard backing, which it looks like it might be, you would just switch out to a standard drill bit once you have gotten through the stone and feel the material change to finish things off. It would be worthwhile starting with a smaller drill bit, such as a 5mm drill bit to punch through, then use a 10mm drill bit to drill back up through the chipboard to connect the hole in the chipboard with the one in the engineered stone. Using this sequence, you will erase the potential for blowout on either side of the benchtop.
Let me know what you think and if you have further questions, please don't hesitate to ask.
Jacob
