gbh first offence

[skyland]

if i get a suspended sentence iam i allowed to leave the country ?

[Busi]

I don't see why not. That is your sentence so they have no reason to withdraw your freedom of movement, you may have difficulty getting a visa to travel to some places.
The main reason to suspend a prison sentence though is in order to complete rehabilitiom programmes such as probation or community service. This will require you to turn up and if you fail to then they send you to prison. If you tell them that you intend to travel and they have these things planned for you then the prosecution may apply to the court for you to turn over your passport as a possible flight risk. Without further detail it is difficult to tell exactly. But a suspended sentence alone does not bar you from leaving the Uk