Start digging and get underground.
Ambient temperatures a few feet down are usually around 54 degrees or so.
And maybe Elvis was onto something when he lined hotel room walls with aluminum foil.

Tin foil suits man. Yes 145 degrees would be too hot for people to survive outside.

I know I'd die, becase I cannot imagine chowing on cactus for three meals a day..

I think anyone with a lick of common sense about them could probably survive the initial onslaught in such a scenario, but the destruction of crops, animals, and environment would still be a death blow. Crops would be ravaged and burned by the heat. Forest, grass, and bush fires would be global, and any animal exposed over those days would perish. As bad as that is, long term would be worse than short term. Several billion people and whichever animals survived facing starvation is not a Fun Time. A global temperature spike like that would mark an extinction event.

Here in the Caribbean its getting hotter and hotter these last years.
Last July was so hot, even sitting on the porch in the shade was no fun anyore. Going to the beach was something you do at night.
So I don't even want to think about those high temps. We have no caves to speak of and the round is too hard rocky) to go underground.

So maybe Antartica would be nice? Lots of space there.

So, assuming the water was still on, could you continually douse yourself with cold water and live in the basement? And why is it saunas are usually between 180-250 degrees F and you don't see people dying in them (well, not very often)?

In my area I would rely on one of the many caves around here and stay underground.

I would imagine you could venture out at night with the only downfall being high heat still. At night you wouldn't have the solar radiation or burns.

I know of a few underground springs that hopefully wouldn't dry up.

With soil you could plant some crops inside the cave close enough to the entrance to get some sunlight but inside far enough to stay out of the heat? Plant mushrooms inside the cave?

If the temps sustained that level for very long it wouldn't matter probably.

I have enough dry goods stored to last almost 2 years & 5-6 months of canned goods.

Assuming I could get them there so I could live on that in the cave but would have to plant crops eventually.

Rice, beans, pasta O boy!!

AC units can be operated from generators, as well as Ice Machines I suppose.