Buy a sound card and speakers. Install, or have someone else install, the sound card. Install any software that came with the speakers or the sound card. Turn speakers on.
First you have connect the sound card drive correctly and installed and you have connect the speaker cable correctly for the drive and you have select control panel from my computer and select the sounds options and you have check sounds properly and you have installed sounds in your computer
Install a sound card and speakers in the computer if you don't have them. Check device manager. Find drivers on the manufacturer's website. Install the drivers for the sound card.