you Downloaded firmware for Huawei P20 Pro CLT-AL01 with build CLT-TL00C01B152 (8.1.0.152),CLT-TL01C01B152 (8.1.0.152),CLT-AL00C01B152 (8.1.0.152),CLT-AL01C01B152 (8.1.0.152)
Huawei P20 Pro CLT-AL01 Published on Released 2018, April . with Android 8.1, up to Android 9.0; EMUI 9.
Display size on Huawei P20 Pro is 6.1" and the resolution is 1080x2240 pixels

You can flash The Stock firmware of CLT-AL01 using This Guide.
more about Huawei P20 Pro Dual SIM CLT-AL01:

this model of huawei powerd by Octa-core (4x2.4 GHz Cortex-A73 & 4x1.8 GHz Cortex-A53) and the internal storage size and ram size is 256GB storage, no card slot.
also it can support No.
besides it can support Single SIM (Nano-SIM) or Dual SIM (Nano-SIM, dual stand-by) .
the Gpu chip model is Mali-G72 MP12 and also the Chipset model used on this model is Hisilicon Kirin 970
The camera on the Huawei CLT-AL01 comes with and support 2160p video pixles.