On Electrum GUI, click on view -> check ✔️ coins. On the GUI, coins will appear. Click on coins to see your UTXOs. Right click on any UTXO and this will appear:
You can use it to freeze any UTXO or UTXOs.
To spend, paste the recipient address on the send tab -> click on coins -> right click on each an UTXO and that image to appear -> click on add to coin control and it would be marked in green. Use this to select all the UTXOs that you want to spend. Right click on any highlighted UTXO which will indicate all UTXOs that you want to spend -> click on fully spend -> send to address in clipboard.