You’ll be using string manipulation a LOT, so it’s wise to get acquinted with it
Trim: removes leading or trailing spaces from a trim, or any other character (you can specify that as a parameter)
Substring: takes a part of the string, starting at your preferred index and then going for an x amount of characters. For example, if you have a string “Hello World” and you just want “Hello”, you’d work with: yourString.Substring(0, 5)
Remove: basically works the opposite way of substring. Where in substring you specify the part you want to keep, in remove you specify the part you want to get rid of.
Replace: replaces a part of the string with another string.
And I don’t know Slip, I don’t think that’s part of Visual Basic, the language UiPath uses.
For more info, visit the Microsoft Documentation on Visual Basic. And of course practise a lot, that’s the best way to get to know it.