How do I grow bonsai trees?

You’ll need to select a specimen that appreciates your climate, first.

The soil should be amended to be acidic, not alkaline and the hole depth is to be twice the size of the rootball, both directions.

The soil should be loamy.

If you’re planning on training the bonsai, from scratch, that is an art not easily covetable here.

all plants require drainage or the roots rot; there are literally hundreds of plants that are used as"Bonsai" some are grown on rocks w/minimal potting soil; What kind of plant are you thinking of growing/using to create a Bonsai? That will determine what growing conditions you need to provide. Pine or Fir trees,Ornamental trees or shrubs,Flowering trees or shrubs,Succulents such as Jade,Roses. Bonsai is considered an art form bon·sai/bänˈsī,ˈbänˌsī/noun

1-an ornamental tree or shrub grown in a pot and artificially prevented from reaching its normal size. 2-the art of growing ornamental, artificially dwarfed trees or shrubs.The word “Bon-sai” (often misspelled as bonzai or banzai) is a Japanese term which, literally translated, means “planted in a container”. ... Bonsai are not genetically dwarfed plants, in fact, any tree species can be used to grow one. noun, plural bon·sai.

a tree or shrub that has been dwarfed, as by pruning the roots and pinching, and is grown in a pot or other container andtrained to produce a desired shape or effect.

the art or hobby of developing and growing such a plant or plants. here are bunch of sies stuff to read to help you choose and get started https://www.google.com/search?q=easiest+Bonsai+for+strarters&rlz=1C1CHBF_enUS750US750&oq=easiest+Bonsai+for+strarters+&aqs=chrome..69i57j0l2.11343j1j7&sourceid=chrome&ie=UTF-8

https://www.bonsaiempire.com/basics

This will give basic info. For quick start there are many kits available at Amazon Hobby Lobby, Home Depot and other places.