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It looks very like the UK pound which should be on your currency formatting list:
but if that's not suitable then you can create a custom format:
First, according to this site: https://symbolhippo.com/lira-symbol/ the code is 8356, so in a temporary cell in Excel use the formula
=UNICHAR(8356)
which will give you your symbol:
Then copy/Paste-special values this result into another cell. Then select that character in that cell and Ctrl+c to copy it to the clipboard.
Now select the cells you want to format and go into Format Cells and choose the nearest Currency or Accounting format you want, including how you want negative amounts to appear:
but BEFORE you click on OK, choose Custom in the Categories, and replace wherever you see a currency symbol, paste in the Lira symbol (I've done it on 1 instance in the picture below):
Then click OK. After that the custom formatting will appear at the bottom of your custom formatting list for any other cells you want to apply the same formatting to.: