Welcome to the forum.
The selection in Peplink is quite large as you have probably found, probably why you are asking!
For what you have written you will be looking at the Balance series, for Home/small office, these you tend to find in the Velocity group of products.
The Balance 20 that @AskTim mentioned is a popular unit and probably the most affordable one, it has 3 WAN port and 4 LAN ports. This most likely means you will need a switch for the extra devices that you have, that are not wireless. It has a 150Mbps throughput, normally enough for home or small office.
You mention that you wish to grow, so I would go for a slightly better throughput model, like the Balance One, which has 600Mbps throughput, 2 WAN ports and 8 LAN ports. (There is a Balance Two model as well, with higher performance but only 4 LAN ports).
An alternative with some resilience buildt in for you is the Balance 30 LTE. although only 200Mbps throughput, it has a LTE(4G) modem built in which you can use as fail-over (or extra WAN connectivity) in case your wired connections fail. It has also 2 WAN ports and 4 LAN ports.
All of them can create vlans so you can segregate the network as you want. But remember that any switch you connect will also need to be managed / vlan capable!
To go more detailed, we indeed need more information. i.e. what the cable/adsl connection actually give you for throughput, and what your future aspirations are. How many wired devices and how you connect them. Are you in need of failover/bandwidth smoothing/network resilience/VPN services?
PM me if you want to go into more details, or post your further questions here. we are happy to help!