Drinkable, running water in your home.

Modern sewage management is a medical miracle.

my mother always says that everything other than a home, food, water and human interaction is a luxury. she says with that mindset you learn to appreciate everything.

but to answer what u asked for: electricity. the absolute brittleness of the electric system, especially with what is going on with dismantling public infrastructure over in the US, it's a great reminder that as normal as we see electricity, it's a luxury dependent on the duty and diligence of tens if not hundreds of thousands of workers all around the world

Having all kinds of food availiable almost instantly. You want to have a yoghurt with fruit in the middle of winter? No problem, just go to the store and buy one. You want to have some fancy food that a hundred years ago wouldn't be even known of? You can buy it relatively cheaply today.

In the 18th century people showed off pineapples because they were so rare and hard to come by.

Citizenship in a country that's not trying to kill you

Having sane, honest, intelligent people in your life.

Clean water, and sanitation. Most places in the world does not even use toilet paper.

Also biologics medication to treat many diseases that don't have medications that were effective before, like psoriasis and eczema, topical had only a temporary effect before it causes side effects.

Having easy access to clean water. In sub-Saharan Africa for example, 300+ million people regularly risk disease and death just from trying to be hydrated

Fresh drinking water

Electricity

Democracy

Living past childhood.

Yes, lots of people feel their lives are awful, but compared to material living conditions even a few hundred years years ago nearly half of all children died before reaching adulthood, and the vast majority of the rest lived harder, more grueling lives than our own, with more illness and injury than us.

Time. You can never guarantee that you have more of it because life is sometimes cruel.

one I think about a lot: having abundant hot water (for cooking, showers, baths, cleaning, etc.)

and echoing what others have said, having abundant potable water.

I also haven't ever experienced a famine in my life - I have experienced more food security than most generations before me. (For me the worst case experiences were eating food that was thrown away, not eating weeds from the yard because my belly hasn't had any food in a week.)

Tea. Coffee.

A lot of recipes online take it for granted that you have access to a wide variety of ingredients and ethnic stores. I live in a small town with one small Hispanic grocery and ordering stuff online is expensive.

Microwave ovens.

Cold milk

Loo Roll.

Comfy socks

Not being into politics.