Is it possible to do SIP in mutual fund using Central bank of India net banking?

For SIP you have to register authorisation to debit your bank account every month(or as per the periodicity selection) with the Mutual Fund at the time of buying the fund at initial time itself. This is called NACH mandate. There is/are specific forms for the same. Once that is given to the MF, the mandate (authorisation) is transmitted to the bank and the bank accepts it after verifying the signature of the account holder and the account details in the authorisation document. (There is provision for e-mandate also).

If everything is okay,from then on your responsibility is to ensure that sufficient balance for the SIP amount is available in your account on the SIP due date. The amount is debited from your account on the pre-specified due dates for SIP by you through NACH- National Automated Clearing House

You ned not do anything separately with your net banking facility in this regard.

You can do SIP payment through net banking of Central bank of India net banking provided if you are having an account is any branch of Central bank of India in Mumbai and you should have permission for online banking. You said that you are having an online banking facility.
Cent BillPay is the facility for that. you can pay your bills and make other payments online. Through Cent BillPay you can now make all Your Payments at a Single Location. But as on date this facility is available only in Mumbai. The bank says that they will introduce this facility shortly in Delhi, Pune, Ahmedabad, Bangalore, Chennai, Hyderabad and Kolkata. Alternatively from their website, you can download the Cent BillPay application and fill it and submit the same in your branch. Then the branch will add your billers through the Cent BillPay.
Alternatively, you can do the same through offline mode. You have to obtain the form required for starting the SIP from the fund house or downloaded it from the fund website. Along with that, an auto-debit NACH mandate is also to be filled. A copy of a cancelled cheque should be attached along with KYC documents – address and ID proof. These documents should be submitted to the fund house branch that is available in your place. They will submit the NACH mandate to the concerned bank. Then the bank will start deducting from your account after obtaining confirmation from you.

The following are the detailed steps to be observed if you want to remain invested in the mutual fund through Central Bank of India, net banking. Details are given below-
1) The investor would be required to fill up the physical form enclosing proofs by means of Aadhar and PAN Card, payment procedures reflecting their interest to take up SIP account of a mutual fund.
2) A URN would be generated after all the informations are filled up and submitted. The investor would receive a message through email I'd in their registered mobile no.
3) The investor would be required to access the mutual fund website and has to fill up the online SIP form, personal details such as PAN, Bank Account No and SIP related details. Ensure that the details incorporated are correct otherwise you cannot open the SIP account.
4) A URN is generated after furnishing all the informations. It will finally reach to the customers through the investor's email I'd.
5) Within a couple of days say within ten days, URN will be generated. This URN has to be entered in case of any transaction. Once the biller details are furnished, the investor can offer auto debit instructions for SIP instalments.
6) I - SIP registration process is meant for a single SIP instruction. For any other scheme related to mutual fund, a separate registration process would be required.

If it is not available in the online menu then you have to give mandate to the bank in the prescribed form online or offline as they guide you for this. Once you give an authorisation to them to deduct that much amount every month from your account and send to the MF company account then they will do it regularly. It is already being done by the banks in general in respect of many monthly bills like electricity, house maintenance etc. The only thing is that you should have an account in the concerned bank (in your case it is Central Bank of India) where money should be available for the payment to SIP scheme on the date it is due for payment.
When you invest in any MF-SIP scheme then either you do it through your demat account in any bank / financial company or through the MF site or through an agent by filling an application form for buying MF units. In all these modes you will find a step for mentioning the bank account from where the money is to be collected every month for sustaining and continuing the MF-SIP scheme. If you have missed that while applying for MF-SIP units last time then it can be revived now by including it either by going to the MF site and registering there as a customer.
I am assuming that you have already invested and now searching as how to make your bank pay for it every month. If you have not invested so far in MF-SIP and want to invest now then include this 'automatic collection every month' thing in your application itself to avoid any inconvenience later.