Why do we need to select 2 times from spinner?

move your if statement into the AfterSelecting event, see also the documentation User Interface

also you might want to do some tutorials to learn the basics... it seems to be, there is a lack of understanding, how everything works...

also see tip 1 here

A very good way to learn App Inventor is to read the free Inventor's Manual here in the AI2 free online eBook App Inventor 2 Book: Create Your Own Android Apps ... the links are at the bottom of the Web page. The book 'teaches' users how to program with AI2 blocks.
There is a free programming course here Course In A Box and the aia files for the projects in the book are here: App Inventor 2 Book: Create Your Own Android Apps
How to do a lot of basic things with App Inventor are described here: How do you...? .

Also do the tutorials Our Tutorials! to learn the basics of App Inventor, then try something and follow the Top 5 Tips: How to learn App Inventor

Taifun


Trying to push the limits! Snippets, Tutorials and Extensions from Pura Vida Apps by

Taifun.