Complete Installation of NFT Marketplace

I have a NFT Marketplace site at www.celebart.io where the frontend has been installed but the backend needs repair. The issue from what I have been told are errors in the Node.js. I need someone who can fix these errors and get the marketplace fully functioning. The primary blockchain I need is Solana. The secondary Blockchain is Ethereum. The budget has been set and will not be increased. Do not answer this request if you cannot complete within budget. I need the site completed as soon as possible.