I want to buy a router with SIM card

Hello! I'm writing through a translator! Please tell me what to buy a portable wi-fi router powered by a SIM card and so that you can put socks on it!
I am grateful for your attention!

Nobody can answer this with the information provided. SIM cards activate cellular modems which communicate on a number of different channels. Different countries (EU vs US vs China) have different channels. Within a country, for example the U.S., Verizon uses different bands than ATT.

So you need to see what channels are available in your area and buy equipment that supports it.

in my opinion because you will need a subscription:
a cheap used smartphone with USB-C
a gigabits USB-C / LAN - RJ45 adapter connected to a hub or a router