>>What is the make/model of the Lenovo? Can you post pic(s) of the label(s) on the bottom of the computer?
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>Ideapad 3

There seems to be several versions, IOW ideapad 3 isn't the whole name. Anyway, according to the manual I found at https://download.lenovo.com/consumer/mobiles_pub/ideapad3_ug_202001_en.pdf it doesn't have a RJ45 conenctor. This means that you must either live with a wireless connection, or buy an adapter. Google "usb 3.2 rj45 adapter" and pick and choose.