No, don't give up. A working machine with Windows 7 is an important resorces, even if something does not work well.
You can fix for about $10.
The OP does not have to fix the internal NIC. Just get something that works on USB. Found on Amazon
for "usb to ethernet"
Cable Matters 202023 USB 2.0 to 10/100 Fast Ethernet Network Adapter (Black)by Cable Matters
$9.99 was $17.99 Prime 4.3 out
of 5 stars 1,679
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for "usb to wifi"
Edimax EW-7811Un 150Mbps 11n Wi-Fi USB Adapter, Nano Size Lets You Plug it and Forget it, Ideal for Raspberry...by Edimax
$8.99 was $14.99Prime 4 out of 5 stars 6,572