Multiple javascript in blocks

Hi,
I need to add 3 scripts (jquery.min.js ; isotope.pkgd.js ; pagescript.js) to a custom block for wordpress (a product portfolio filtered grid).
I found Is this a sensible method for adding multiple Scripts and CSS files to your Custom Blocks? … but I just can’t understand the meaning of what I read in the post, too much knowledge is taken for granted.
I am a beginner and I have not found any documentation to help me.
Is there a comprehensive tutorial that allows me to address and solve this need?
Thanks in advance.
Giallu.