I second this, don't go out buying a expensive tent/gear first go around. Just get a basic tent from a big box store, check the weather before hand and just see how you like it. At the same time don't get the cheapest and have it break on you causing a bad time and possibly turning you off the hobby. Here's some options for a decent entry tent.
I'll echo what u/avitar35 said above.
For tent, get the Coleman Sundome 3 person
https://www.amazon.com/Coleman-4-Person-Camping-Sundome-Setup/dp/B019N9W6EQ/?th=1&psc=1
You need a good sleeping pad and sleeping bag rated at least 30 or lower. Nights in desert climate can get much colder than what shows on the weather report.
Air mattress will not provide any insulation. You can get something like this:
https://www.rei.com/product/199745/kelty-mistral-20-sleeping-bag-mens
https://www.rei.com/product/191448/sea-to-summit-camp-self-inflating-sleeping-pad-rectangular
https://www.amazon.com/dp/B019N9W6EQ/ref=cm_sw_r_cp_apa_i_383pFbWV7398K
Decently light weight, can choose whatever size you want(2 3 4 6). Will definitely hold up for only a few trips a year.