How can i store values in of my input fields then use them to log in after account is created?

Can i do this with pure JS? when i think about it it seems easy but then... Google isnt helping because what i try wont work. I just want to enter in a name, an email, and a password, then switch to a new page where you can log in.. Cant attach file so heres the link, i think... https://code.sololearn.com/Ww63L6S386hm/#html