Cam timing requires engine disassembly on small engines and it's either right or wrong.

You could be off on ignition timing if you sheared the key on the flywheel which then requires the flywheel to be removed to replace the key.

Make sure it's not something simple before you go deeper into the problem. Gas/fuel delivery, dirty carb, bad spark plug, all the safeties not made.

You did not actually state what the problem is. Cam timing requires engine disassembly on small engines and it's either right or wrong.
You could be off on ignition timing if you sheared the key on the flywheel which then requires the flywheel to be removed to replace the key.
Make sure it's not something simple before you go deeper into the problem. Gas/fuel delivery, dirty carb, bad spark plug, all the safeties not made.
You did not actually state what the problem is.