Homelab

Without the model it’s hard to help you. It would be best to give us the model, then we will see if this is a sfp or sfp+ port. With sfp you are still limited to 1G. And even if it’s sfp+ and you connect your nas to it, the user is limited to 1G from the rj45 ports on the switch. So unless there are multiple users using an exzessive amount of bandwidth this will not help you at all.

Just for your information. You need a Gbic which is supported by you switch. This gbic can be with fiber (single or multimode LC) or also RJ45 1G or 10G. There are a lot of options.

Log in and run a "show version" so we can know what exact model it is.

Usually even the manufacturer of the switch only guarantees functionality with a subset of SFP modules. The safest bet is to look for the manufacturer qualified device list and choose the cheapest module, that still satisfies your requirements. Maximum length of fibre cable and throughput will be the deciding factors.
Note that, unless your cable is many kilometers long, you do not need an 1GB SFP. 1GB can be easily transfered via twisted pair ethernet.
You probably want a 10G, short range (<1km) SFP module.
Once you have found one, buy an identical one for the other side, don't mix.

Figure out the model of the switch and go read the documentation.