Quote from: pxstein on June 03, 2018, 10:09:39 AM

Now I want to send an amount of 0.0000600 Bitcoin (plus fees) to someone else.

How do I tell Electrum from which of my addresses the amount (resp.how much) should be taken?
How do I tell Eletrum from which of my addresses the (currently unknown) fees should be taken?

You have two options...

Option 1. Don't do anything and let Electrum work it all out for you... It will pick UTXOs as required to cover the amount to send + fees automatically.

Option 2. Use the "Coin Control" features of Electrum:
- 2a: use the "Coins" tab (View -> Show Coins)... this lists all the UTXOs in your wallet, and you can pick and choose which ones you want to include. Then right click and select "Spend".
- 2b: use the "Addresses" tab (View -> Show Addresses)... You can see which of your addresses have a balance. Select which ones you want to include, then right click and select "Spend From".

Note that Electrum doesn't treat the amount to send and fees individually... it sums them up into one value.