even though it can have a greater expense attached to it (with trunking, the cables and patch ports) I would highly recommend using cable. It is more reliable and secure for your business.
I would also recommend seeking a local company that can help with this as depending on what you wish to do with your network will greatly determin the level of knowledge that you would need to acheive this.
For basic internet you would need a router and a switch with enough ports to allow all of the cables to get a connection. After that if you’re unsure seek external company to help.
A healthy mix of both wired and wireless networking would be the most flexible solution
For wired, as mentioned, you will need some sort of routing (Layer 3 switch, router, etc) and 1-2 switches for your users and other end devices.
It is possible to cable the desktops, printers and other “stationary” devices into either cable drops to them – or, if you go a bit more professional – wall jacks that wire into a patch panel or 2
For wireless, 1 – 2 WAPs (wireless access points) at – for example – opposite ends of the office would allow for connectivity of laptops, smart phones, Tablet PCs (iPads, Android tablets) for your users, clients and guests
Best answer in any IT environment: “It depends”. It is reliant on what you want to do, what you need to have and how much time and capital you’re able to invest in it…