Trouble Codes + possible knocking? Help

[Rasheid]

The codes you're seeing are definitely related to emissions. P0455 is about a large evaporative emission system leak (like a loose or faulty gas cap, or a broken evap hose), P2096 suggests the car is running too lean (this could be due to issues like a vacuum leak, exhaust leak, or problems with the oxygen sensors), and P0441 indicates a problem with the evaporative emission system purge flow.

Here's what I'd recommend:
Make sure the gas cap it's on tight and in good condition. If it looks old or worn, replacing it can be a quick and cheap fix.
Check for any obvious leaks in the vacuum lines and hoses around the engine. You might also want to check around the fuel tank and charcoal canister area for any signs of damage or loose connections.
Considering the P2096 code, checking the oxygen sensors could help. If they're faulty, they could be sending the wrong data, making the car run lean.

As a refference, you might search for causes and solutions on this trouble codes blog.