Need advice on NAS build to replace WD My Cloud NAS

[Enquiries]

I recently bought this motherboard CPU combo.
ASRock J5040-itx - Intel Quad-Core Pentium Processor J5040 (up to 3.2 GHz)

8 or 16 GB of Ram

I also have two - WD Red 2TB NAS Internal Hard Drive - 5400 RPM Class, SATA 6Gb/s, SMR, 256MB Cache, 3.5" - WD20EFAX. ---these drives were bought 9/2019 and used in the My Cloud EX2 Ultra.

This is to be used as a home NAS, mostly just to store files. I plan on using TrueNAS

Questions:
1) is that MB/CPU enough? Ram?
2) are these drives worth reusing?
3) if I can use them, I'm thinking about buying 4TD drives. Can I use them with the 2TB drives I already have? Or is it better to but only use 4TB drives.
4) I have an older 60GB 2.5 SSD. I'm thinking about using as a boot/OS drive. Is this OK? I have other SSD drives of larger sizes. Just trying to make use of this drive.
5) I may add two more Sata connectors through a pcie x1 card. Is this OK to use or is this not advised with TrueNAS?

[ed]

The ASRock J5040-itx with an Intel Quad-Core Pentium Processor J5040 and 8-16GB of RAM is sufficient for a home NAS, mostly for storing files.
Yes, the WD Red 2TB NAS Internal Hard Drives that you already have can be reused. However, please note that these drives use Shingled Magnetic Recording (SMR) technology, which is not ideal for all use cases. It is recommended to use CMR drives for RAID configurations or write-intensive workloads.
You can use 4TB drives with the 2TB drives you already have, but it is not recommended to mix SMR and CMR drives in the same RAID configuration. It is better to use only CMR drives if you plan to use them in a RAID setup.
It is fine to use the 60GB 2.5 SSD as a boot/OS drive, but it may not provide enough space for future upgrades or expansion. If you have larger SSD drives available, it would be better to use one of those.
It is generally okay to use a PCIe x1 card to add additional SATA connectors for TrueNAS, but make sure that the card is compatible with the motherboard and the operating system. It is also important to use quality hardware from reputable brands to ensure stability and reliability of the system.

Here is more https://www.truenas.com/docs/core/gettin...wareguide/