How can I get a backyard pool?

Local codes and ordinances would be the first place to start. If it is even legal to do so and if your property can support a pool (in ground I suppose) since you’re saying luxurious .Then finances and contractors licensed to do said work and of course inspectors. Yeah all this kinda takes the fun out of it.

First of all, you gotta dig a BIG hole…
But I would contact a contractor.

Well keep in mind pools do take a bit of upkeep work and maintenance. You might have to think on how worth it really is, or maybe just do a hot tub instead? If you really want to still, ask a pool contractor company first and see what all the steps and codes will be. You will have to hire someone to do the work of putting it in. My apartment building use to have a small pool. They took it out about 20 years ago due to the hot water heater for it broke, plus the upkeep, and liability was too much, with the new building owner. I do hear you though having your own private pool would be nice! I love going to our city public pool a block away. I just don’t like the crowd.
Yes, it’s possible, as long as you are okay and ready for the hoops and work to have it put in and take care of.

The least expensive is above ground.

Next are the inground fiberglass or vinyl.

Lastly, are concrete pools, we usually call them gunite.

Maybe there are more options I don’t know about.

For an inground pool you need to make sure you have buildable space on your property. You’ll need to see a survey and look at the setbacks, etc. above ground you might have more flexibility, but my guess is it still needs to be within the building envelope.

If all you want to do is cool off and not swim, you could look into getting a spa/jacuzzi.

Cost is a big factor. Additionally where you live is another.
Inground versus Above ground. Space on your property is a consideration. Local codes are also a factor.
Homeowners Insurance will also add a twist.
Your ability to maintain will be a factor on the pool, filter, etc. Salt versus chlorine.
I appreciate your desire. Make sure you know what you are in for.
I have owned many homes with many types of pools and equipment. I have loved them all, and maintained them all.
It is a big investment in $$$ and time.
What type of pool are you thinking? What area do you live?

Listen to me now and believe me later.
Getting a pool is one of the worst mistakes a person can ever make.
It’s a massive money drain. There are always problems on top of the normal maintenance it takes.
The two happiest days in a pool owner’s life are: The day s/he gets the pool… and the day s/he gets rid of the pool.
If you want to spend $100,000 over the next 20 years, get a pool.