Hey Zeid,
Welcome to the community! 
If you are looking to keep your number, the best option will be to change your account to prepaid and do a refill. You can keep your number for 1 year after a refill is done.
If you want to keep your current plan, you can lend the phone to someone while abroad but you will be responsible for the account and invoices. You can always do a transfer of responsibility to that person if you don't want the hassle of being responsible for the account.
I'll send you a PM to check out your best options. 
