You need a plumber. Do you have a friend? Can you make friends with a plumber?
You need a specific set of tools for each part of the job. You need to select from hundreds of tools, fittings, and pipes.
Learning without an apprenticeship or tech school class means learning one step at a time with a lot of do-overs. On the other hand, there is no substitute for hands on experimenting.
Original PEX plumbing used crimped rings to fasten ends to fittings. You need a crimping tool with jaws to fit the tube you are using. You need the correct size ring. All fittings and tubing need to be designed to work together.
https://www.thespruce.com/installing-pex-tubing-2718684
https://duckduckgo.com/?t=ffab&q=pex...llation&ia=web
Purpose designed tubing cutters are essential.
The most important tool is your head. A good head for mechanical things makes all the difference.
Today, there are other ways to work with PEX. One of the good DIY methods is to use "sharkbite" fittings. They are easier for beginners to manage.
https://www.sharkbite.com/us/en/prod...ontent=General
Start by selecting a system to use at your local big box home store. Buy tools and materials. Experiment until you think you have it down. Then begin the project. Plan for do-overs. Inspect for leaks immediately and later to see if things hold.
Assume you will make mistakes. Assume you will end up with tools you did not need. Assume you will end up without tool you do need.
Menard's often employs retired plumbers. The plumbers love to give people advice and know exactly where to find any given tool or fitting. Home Depot, not so much.
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