In addition to separating cells, combining cells you can also use tools in the Tables Tools section, but you should use the mouse to manipulate faster.
To split a table into 2 tables, place your cursor on the part you want to split then go to Table Tools -> Split Table
But after separating maybe 2 tables will be nested, you have to select the table and drag it out, this is the result
Want to merge 2 tables you have to cut the current table, then put the cursor in the last box and then press Ctrl + V