after remodeling was done hood felt and we found out about horrible electrical and gas plumbing work how can we sue our contractor?

Yes. If you hired us, the first step would be to get a written estimate from a licensed contractor, with descriptions of all of the defective work, the work required to fix it, and an estimate of the cost. We would then include that in a letter demanding that he agree to pay that amount. If the cost were less than $10,000.00, you could sue him in small claims court without an attorney. It sounds like more. If you have a written contract, and the contract includes a provision for reimbursement of legal fees, then the demand letter would include the threat that you will not compromise and will take the case to trial in order to obtain a judgment which includes reimbursement for all your legal fees.