It is unfortunate that your attorney did not provide the level of representation you expected at trial. If you believe their performance was so poor that it affected the outcome of the trial, then you may be able to file an appeal based on ineffective assistance of counsel.
In order to prove ineffective assistance of counsel, you will need to show that your attorney’s performance fell below an accepted standard of care and that it resulted in a different outcome than would have occurred if they had performed adequately. You will also need to demonstrate that the outcome was actually prejudiced by their inadequate performance. This can be difficult to prove, so it is important to gather evidence such as witness statements and other documents related to the case.
You should speak with an experienced appellate attorney who can review your case and advise you on whether or not filing an appeal based on ineffective assistance of counsel is viable.