My internet connection is around 300mbps, and it is doing great, but the same way it keeps downloading 0,03% per hour... What can I do for optimizing this process ?? Just gotta download this and it won't work this by this speed.
Don't worry too much about that 0.03% per hour rate, it tends to underestimate a lot.
For reference, when I'm catching up my node to the tip with about 7 days worth of blocks to download, it'll show me that it would take 2 days to sync at a rate that's close to yours,
but in reality, it always only takes an hour to finish.
But aside from that, your setup is really getting a bottleneck with that external hard drive as others have mentioned.
Follow their suggestion if you want faster sync speed.
You may also want to check if you're connected to enough peers to download the blockchain from since in some cases, nodes cannot connect to others.