Drupal 8.x

I am attempting to create a Base Theme. I have all the necessary files, I have managed to create Themes that use others as a base theme (Classy, et.al.), and have not had this issue; however, when I attempt to move my new theme into my Drupal 8 setup, I get the famous "The website encountered an unexpected error. Please try again later." Error message. Checking the logs, I find
 

Here is one of two drupal homepage I have. This is a hobby and interest page. working on teaching me to rebuild this one way or another. the hope is to keep it as somewhat as it is today. hope to do it yourself. also want to be able to have web form set up against the page, but here I have a challenge that something drives to make xx number of flexbox when I go in to end or make a new one. this work is put on hold. for I do not want to destroy the database I have now. I think drupel is one of the better platforms to use for this website.

Hello, 

Maintenance mode is on but my site is live. 

I can see home and login pages just fine. Rest of the pages are not live. 

Why do I see the home and login pages when maintenance mode is on?

Thanks!

We are looking to hire a developer to assist in a Drupal 8 project that involves taking Excel spreadsheets of data and importing/uploading it into Drupal 8 to create entities. There are several sheets and they all have different formats/layouts/headers/etc. Samples can be provided.

We already have this working using Feeds Import, but we believe a custom module may be necessary to manipulate more complex spreadsheets before Drupal can process it and this is where we need assistance.

How do I create a form like the one below on the rest webform ?