iwantmyhomepaidwithbtc2 was right. In the /media folder I found the disks. Linux is so different from Windows. I didn't know that.
I also moved the chainstate folder from HDD to SDD and created a symlink. Now it's downloading twice faster.
I'm grateful to everyone who help me on this topic.
Cheers!

Maybe I have used the words "external" and "partition" wrong. I'm not a techie person.
I've read all of your replies, I appreciate your efforts to help me.
I will try all of them today or tomorrow morning, and will tell you how it went. Wish me luck.
If anyone has other ideas, please let them here.
Thank you brothers!

Yes, Software Store. Maybe, there is a configuration file, but I had not chosen a directory for blockchain to install before.

LoyceV, you misunderstood my problem. I want to run a full node, not a pruned one. I know how to install each one. I ran a full node in the past, I know how to install and configure it. I also did the trick with symlink for chainstate on ssd. My 1TB HDD is already formatted and I plan to use it just for Bitcoin Core. My hdd's and ssd are connected through SATA, not USB.

My problem is that, unlike windows btc core installer, where I could choose any partition I wanted, the linux btc core installer sees only the partition where the os is installed.

Thank you for your answer I will try when I'll be home.

I tried 3 ways to install it. From snap, bitcoin.org, and default linux store.
For the first two I get the same result. For the last, it skips the window where I can choose the directory, and it's downloading the blockchain in the default directory.

https://ibb.co/3RL6kvp - This is what is displayed.
https://ibb.co/Xxpk01H

I don't have /media (or at least I don't see it). In the "Look in" window is just "Computer" (where linux is installed).
And in the left windows is "Computer" and User (/home/user). Dragos in my case.
The HDD's are not displayed.

I don't know commands in linux, like lsblk, that's why I asked a step-by-step solution. Because I'm new in linux.
Thanks.

Hello everyone.

I tried to find a solution, but I didn't find a step-by-step one.

I'm using Linux (Zorin - based on Ubuntu) on a 256 GB SSD. I want to install the blockchain on a separate 1 TB HDD. ( I have 2 HDD's)
The problem is that although I can access the HDD's from the OS, they are not seen when I want to install the blockchain.

How can I solve the problem? Step-by-step, please. Not just "Give permission to the app" or something like this. This is my first time using Linux.

Thank you!

Too technical for me, I will try what you said, I hope that it will work. Thank you!

Thanks for explaining step by step!

In bitcoin core installer there are 2 directory to choose, 1 for btc core and 1 for blockchain (if I remember correctly). I don't know if you consider it as "Welcome screen" or the actual installer. But choosing the directory for blockchain where it is already installed won't work, it will download it again, maybe it overwrites it.

Thank y'all for the information

I don't remember about pruned blockchain, maybe it was just a curiosity.
I use Bitcoin Core just to run a full node.
So I have to write the path to that directory in the bitcoin.conf file.
I thought choosing that path in the installer was enough.
Thanks for your answers!

Hello everyone!
I've changed my computer, and I will make some changes.
On my SSD (240 GB), I will have both windows and linux (dual boot).
Linux will be my main system, so I want to install the bitcoin core in linux format.
Currently I've bitcoin core on my HDD, but it is windows format (.exe).
I want to uninstall and reinstall it, but this time in linux format.

Will I lose the blockchain?
Once, I deleted the bitcoin core, kept the blockchain, reinstalled the bitcoin core and chose the same folders, but the blockchain started to re-download, although it was already on my computer.

Does anybody know how to proper uninstall bitcoin core (windows format) and reinstall it in linux format, but not the app starting to download the blockchain again?

Thank you!

I will be looking to see who's accepting bitcoin in LN.
LoyceV, I didn't know that algorithm. I think I will donate 6$ twice a year.
Thank you. 

I use bitcoin for donations (I'd use it for purchases too if I could find shops accepting it) and after a big sum received they will transfer the money, so every dollar counts! So  both of you recommend Litecoin, I will still use bitcoin because I want to support the Bitcoin ecosystem but it's a thing to consider, thanks!

Good to know. I believe that if I want to use LN, the receiver must have LN too, the same thing about altcoins. Do you recommend any specific (valueble) altcoins for this?

Yes, when I posted, it was the same problem like yesterday. Then it repaired. Thanks!

Thank you, nc50lc, for your complex answer.

Update: After more than 24 hours, everything works fine. The payment was transmitted, the transaction isn't invalid anymore and now I can spend my amount.

For everyone having this error, just wait (even a lot of hours) until everything solves itself.

Hello, I have big glitch in my bitcoin wallet. I sent a transaction, and after 24 hours it still says "This payment has not been transmitted yet" and I can't spend any of the amount I have (equivalent to $22.57).
Sorry if the question was asked in the past.

https://prnt.sc/f4Vrt8D193j2
https://prnt.sc/lrDNcnE91pVV
https://prnt.sc/71TYYQfKGGIb

How do I solve this?
Thank you!

Hello, I've an old laptop which I can let open 24/7, but it has low storage (160 GB), so I can't run a full node. Does a prune nodes helps the network, if I allow incoming connections?

I will run the other program which requires VPN on VM and keep Bitcoin Core on the main OS.


Of course, thanks!

Well, I guess I can do it, thanks for the idea.
Maybe it can be a cause, I will consider that. Thanks!