I still don't understand what I need to add and where exactly? Could you explain in more detail what needs to be done?)
If your wallet (I assume you use ElectraCore 2.1.3) doesn't sync, because it says it has no connections....
you can look for active connections using the explorer...
https://eca.ccore.online/connectionsthis will show you a list with the ip addresses of the last seen nodes in the format xxx.xxx.xxx.xxx:5817 (you can ignore the 5817 part...)
Now - in the wallet got to ->Tools-->Debuconsole - a command line opens
type addnode xxx.xxx.xxx.xxx add (where xxx.xxx.xxx.xxx stands for one of the addresses of the above list..)
repeat (with other addresses)
usually it should be sufficient to add 5 to 10 nodes, then the wallet should find connections and start to sync...
To avoid having this problem in the future, you should keep the wallet running a few hours after it started to connect, to get as many good connections stored as possible (the wallet will save the connections it could establish in a file called peers.dat) - This should allow it to find connections the next time you take it online...
But to avoid this problem in the future, you should sync your wallet at least one a week, better more frequent, because some of the nodes might go offline in the meantime...