The 2060 is rated at 120W and draws around 115W in real world scenarios (Guru3D Benchmark). Overclocked models can go beyond that, however.
Meanwhile; your PSU provides just 18 Amps on the 12v rail, which means a maximum of 216 watts for both the CPU and the GPU. Plus, casing fans (Especially 120mm ones), motherboard, SATA drives and RAM module also draw some power from the 12V.
Besides; it explicitly says: "Total output power shall not continuously exceed 200W".
I wouldn't trust this PSU. Not even with my cheap and cheerful GT440, let alone a brand new GTX1660!
Throw it in the dumpster. That's where it truly belongs!