The answer to 'how to repair leak repair' is to first identify the source of the leak and then take the appropriate steps to fix it. This may involve patching or replacing damaged shingles, sealing around roof vents or chimneys, or addressing any other issues that are allowing water to enter your home.
The specific steps will depend on the type and location of the leak, but in general, you'll want to inspect your roof thoroughly, clean and prepare the area, apply the appropriate sealant or roofing material, and then test the repair to ensure it's effective. It's important to work safely and use the proper tools and equipment, and to consider calling a professional roofer if the leak is extensive or you're not comfortable with the repair process.