5G WIFI, warining when updating and pc man

[mdre808]

First the least promblematic issue: pcman file manager ( default file manager)never gets update, for years!
2nd, I have home Wifi that provide 2.4g and 5g, the smart phones reciever both while the notebook pc can only get 4g. Why? Because the notebook pc is old?
3rd was used to be an issue, which I was told it did not matter and ignored it. that is after updated, the terminal showed  w (w:) for warnings,  this was a "update-initramfs" issue. in past few years, they were few such warnings, now, they became many. Therefore, is this phenomenon still OK? they used to be "Possible missing firmware... blabla"s mow there is a new one added: "W: No zstd in /usr/bin:/sbin:/bin, using gzip"
I can still work on well , but I wanna know ,at least, why these happened? Thanks.