Hello,

i will write the solution here, if you have a feedback please comment here. Note that before partitioning you need to backup the data.
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My HDD has several partitions and i needed to resize last one which was at the end of the drive. It was bootable Linux system partition.
Some partition managers not given me option to resize it, (it was ext4), but at the end i installed bootable USB flash drive using Rufus or Unetbootin app where i loaded gparted iso on it.

Then in BIOS set USB as a priority boot option on two places, and booted to USB. Selected to launch partition manager gparted in the menu, but it did nothing for a while, then it loaded maybe after 2 minutes.
I was able to resize my sda4 linux system partition, the operation was to "Move /dev/sda4 to the left and grow it from 7.78 GiB to 15.41 Gib.", it warned me i can loose boot menu and i may need reinstalling it etc.

The process took maybe 10 minutes or less on slow HDD. And finished

Maybe i was lucky that i had unallocated space before (on the left from) this partition.

But i rebooted and was able to see boot menu and boot to both OS and it was resized successfully.