Protected workbook, filtering data and going to the first blank line

[dapper1960]

HI - I have no idea what I am doing and just usually use the general excel functions. So please bare with me.

I currently made 2 buttons in my spreadsheet. 1 to go to the first row of data and the next to go to the end or blank row - both in column A. The book isn't that big (only 400 lines). I had to protect it because people were entering data in row 700 or something. I do have a formula in column P that does go down to row 699 and that particular column is protected.

Now the big complaint is that they have to "page" thru all that data to find what they are looking for. If I sort while it is protected, excel crashes .

So I made extra buttons to filter for them but the blank row is hidden, i can't get to it.It seems like all I can do is either go to the next blank line or filter by their name. I don't know how to have it display so they can enter data. Can I do that? utilize both functions? And if Yes, how?
OR should I have a delete blank rows button ?

Thanks in advance for all your help
Just a little admin trying to make someones day easier.