You have posted this in the Timeslips anywhere forum, but I will assume that you were actually using regular Timeslips, but have a Timeslips go license. 
The Import must be done by Someone who has a full license of Timeslips. 
They will need to open Timeslips import. Then choose to create a new template. Select that you were importing in slips, and you will get an option to define the fields to match your spreadsheet. Using the options at the top you can select certain defaults, for example, that the split type is always a time entry.

there is help available in the documentation. Consultants like myself can also provide help but there will usually be a fee for that. 

This is my Timeslips environment. If you could tell me which buttons to click and where to go to upload an .xls/ .csv file, I would greatly appreciate it.

The answer is essentially the same as my reply to your question a year ago here:  How to import .csv documents into the Sage Timeslips system regarding importing into eCenter.

You are posting in the Timeslips Anywhere discussion board, but you seem to be using Timeslips Go (from your post and screenshots.) Timeslips Go does not have the ability to import from a file. It is just a web-based way for timekeepers to create slips. Whomever at your firm that runs the main Timeslips Premium program that your Timeslips Go syncs with would be able to import your file. But since you likely only have access to Timeslips Go, you cannot import them yourself.

Nancy Duhon, Esq.
Duhon Technology Solutions, LLC
Master Certified Consultant for Sage Timeslips
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Providing individual Consultations and Third Party Remote Desktop Support - including older/unsupported versions.
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