There are two different kinds of beeps you can control, the "roger" beep and the "button" beeps. Below is an excerpt from the owners manual explaining the simple procedure.
“Roger” Beeps/Talk Confirmation Tone
When you turn this feature On, your two-way radio transmits a unique tone when
you finish transmitting. It’s like saying “Roger” or “Over” and lets others know
you have finished talking. If the person you are talking to does not hear the talk
confirmation tone, you can enable it by pressing and holding + (plus) as you turn On
your radio. Now, whenever you release the PTT, you let your friends know you have
finished talking by transmitting a “Roger” Beep tone. “Roger” Beeps will be
disabled as the Default Setting.
To toggle the Talk Confirmation Tone feature, turn your radio Off and then
back On while pressing and holding + (plus) .
Every time you press a button on the front of your radio, it beeps unless you turn
Button Beeps Off. To turn Button Beeps Off, turn your radio On while you press - (minus) and
hold . To turn Button Beeps back On, turn the radio Off and then back On again
while you press and hold the - (minus) . On is the Default setting.
Here is a link to the manual: http://www.giantintl.com/RadioPDFs/Outdated%20Manuals/T7100_User_Manual_E.pdf