A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Split Table doesn't exist in Excel, it's a feature in Word only.
https://support.microsoft.com/en-au/office/split-a-table-d231a898-6983-4ef8-acb0-797c7f2b0c45
In Excel you can only merge cells.
There is no simple way to convert Word tables to Excel, you can try to select the table in Word and copy, switch to Excel and paste. In most cases the layout in Excel looks different and it is up to you to adjust it manually.
Andreas.