Slow Internet on the Huawei mate 20 lite?

Hello first I bought the Huawei Mate 20 lite a few days ago, the only problem is that the internet is very slow. But now I do not know if this is on the W-LAN or on the phone, on my old phone it works, but a bit slow. For example, if I want to go to instagram, I need at least four bars to load anything, while three are enough for my old phone. I do not know how to continue

Lite version are always stripped down variants such as the p10 has 2 cameras while the p10 lite only owns the p20 owned 3 cameras while the p20 lite only has 2 as it is also in the hardware there are cheaper or less parts installed that makes the lite versions are cheaper and how well these hardware chip inserts harmonize with each other has not even the manufacturer's influence as there are always parts that run erroneously but long talk short sense the lite devices have always stripped-down performance