How to open a Yii2 application on localhost?

Hello world !
i am new to programming and i really need help am getting out of my mind and i can’t figure it out i just can’t
i paid for a company to make me a website… they can’t finish it so i decided to learn and finish it on my own
so the problem is the website is done on Yii2 framework and it’s really hard to learn it…
how can i access the website ( i have already installed yii2 framework and i have a XAMPP local host setup) in url in my localhost to see it like it’s online
i downloaded the database from the server and i have added it to the localhost data base
what to write in the url ?
i have opened a file called public_html
in the url i wrote : localhost/mysite/…/public_html

i got this
how to open it to see it in the normal shape with all the functions on the localhost server
please help me

Hi, welcome to yii. You should read official documentation.

i have an application which was all ready made in Yii2 i downloaded the file from the server the question is how to run it on localhost not how to install yii2 … i am sorry but your answer did not help me at all or you did not understand what i meant to say… thank you please if you have an answer help me

(Your second topic on this same issue was closed and the title of this topic changed)

In the start guide is mentioned, what you have to do in order to run your yii app on localhost.
Did you even read through it and if yes, where did you have a problem setting it up?