Meanings & examples:

• before something happens → “China unveils Shenzhou 22 mission patch ahead of Tuesday launch” = အင်္ဂါနေ့ လွှတ်တင်မှုမတိုင်ခင်
• earlier than → “China is 1:30 hours ahead of Myanmar”
• in front of / having advantage → “She is ahead of the other runners”