The LEN function returns the number of characters is a cell. It's very useful if you have to check the length of names, codes, references
In Excel it's easy to extract text string with the function LEFT, RIGHT, LEN and MID. Discover how to use them in this article
If you want to remove the extra spaces in a cell, there is a function for that ; it's the TRIM function. But you must convert your formula in values.
The TEXT function is very useful when you have to create a string which mixed text and number or date. You can customize each part of your date
The SEARCH function is very useful when you don't know the position of a character in a string. Look at the example in this page to see how using it.
In Excel 2013 and later, you can extract text without a formula using Flash Fill.FlashFill is a tool integrated into Excel, that runs in the background continuously.
In Excel, it's easy to capitalize the first letter with a function, by VBA or with Power Query. All the techniques explain here.
The new TEXTSPLIT function allows you to split the content of your cell on a delimiter. It's very easy to use.