how can I record my run?

First of all what device are you playing on/able to play on, because if for example it's a Chromebook most options are bad, but a PC you have really good options for.

i guess that what I use is conceded a chromebook.

Is it a good Chromebook or a bad Chromebook or some other Laptop?

it is an acer laptop.

Alright try to download Obs Studio, it is the best free recording software unless you want to pay money.

ok thank you.