How do I buy a house?
That depends where you are. Typically the process is as follows:

1. Check your credit score: This could affect the amount of loan money you can get, changing your budget.
2. Save for a down payment: Traditionally, this is 20% of the house's price, by may change by area or by lender.
3. Get pre-approved for a mortgage: This will help with peace of mind, and you will have a concrete budget to work with. Keep in mind that getting pre-qualification does not give you the promise that the company will lend money to you that pre-approval does.
4. Shop for a home: Whether it be through a real-estate agent or yourself, you can shop around for a home within your budget that meets your needs.
5. Make an offer: Decide how much you want to offer the owner, and formally give them an offer. The paperwork differs based on location, but you may need to write a cheque for "earnest money" at 1-2% which is different from down payment.
6. Get a home inspection: Get a trusted, qualified home inspector to ensure there aren't any surprises waiting for you, like a poorly installed pipe or water damage.
7. Get a home appraisal: Even if you are pre-approved, the lendor will want to have a home inspection to ensure that the house is a good investment. 
8. Head to closing: This is where all the parties will meet and process many forms. This varies highly based on your location, and it is recommended to talk to a local advisor or lawyer beforehand. 
9. Move in: Congratulations! You now have a new house. Take some time to enjoy your life as a new homeowner.