Thank you for answer Cezary.I tried to install f2fs-tools and kmod-fs-f2fs but it was not successful,
it was a mistake libuuid.so.1, libuuid.so.1.3.0 installation canceled.
You can describe me please step by step instructions i am a beginner.
Thank you very much for your time.

Hi when added source in opkg https://downloads.openwrt.org/releases/ … 24kc/base/ package installed sucess but if use mkfs.f2fs /dev/sda1 write this error :
mkfs.f2fs /dev/sda1
/usr/sbin/mkfs.f2fs: line 1:EL@▒4t4: not found
PuTTY/usr/sbin/mkfs.f2fs: line 2: 4@4@4@@t@t@tp▒@▒@p▒@▒@▒@@x▒x▒~▒A~▒A~▒!▒▒@▒@▒@@dt▒Qdt▒R~▒A~▒A~▒
/lib/ld-musl-mips-sf.so.1: not found
PuTTY/usr/sbin/mkfs.f2fs: line 3: d
▒: not found                       pA▒p5~▒A▒@
/usr/sbin/mkfs.f2fs: line 5: syntax error: unexpected "("

Install its ok:opkg update
opkg install f2fs-tools
Preparing to install the following packages, which will require 6656 bytes:
        f2fs-tools

Preparing to install package f2fs-tools...
        Downloading...
        Downloaded f2fs-tools successfully.
        Installing f2fs-tools...
        Successfully installed f2fs-tools.
Installation of packages successful.

root@RBM33:~# opkg install kmod-fs-f2fs
Preparing to install the following packages, which will require 150127 bytes:
        kmod-fs-f2fs

Preparing to install package kmod-fs-f2fs...
        Downloading...
        Downloaded kmod-fs-f2fs successfully.
        Installing kmod-fs-f2fs...
        Successfully installed kmod-fs-f2fs.
Installation of packages successful.

df:Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/root                 6912      6912         0 100% /rom
tmpfs                   126860       504    126356   0% /tmp
/dev/mtdblock9            7296      5084      2212  70% /overlay
overlayfs:/overlay        7296      5084      2212  70% /
tmpfs                      512         0       512   0% /dev
/dev/mmcblk0p1        26777156   5479036  19914872  22% /tmp/usb_mount/0725a517-7900-4ad7-b82f-cb682103c2b1
/dev/sda1              3777592     15256   3550728   0% /tmp/usb_mount/c3072e18-01
/dev/mmcblk0p1        26777156   5479036  19914872  22% /tmp/share_home/Pedros/SHARE

Thank for your answer in your repo package f2fs-tools not exist.
Yes iam add repo https://downloads.openwrt.org/releases/ … 24kc/base/
and install package f2fs-tools from here

ok when I  remove repo https://downloads.openwrt.org/releases/ … 24kc/base/
opkg update
opkg install f2fs-tools
ERROR: No package named f2fs-tools found, try updating your package lists

opkg.conf :
dest root /
dest ram /tmp
dest plugin_root /plugin_root
lists_dir ext /var/opkg-lists
option overlay_root /overlay
# src/gz openwrt_core http://downloads.openwrt.org/releases/1 … 1/packages
src/gz openwrt_base http://downloads.openwrt.org/releases/1 … _24kc/base
src/gz openwrt_luci http://downloads.openwrt.org/releases/1 … _24kc/luci
src/gz openwrt_packages http://downloads.openwrt.org/releases/1 … c/packages
src/gz openwrt_routing http://downloads.openwrt.org/releases/1 … kc/routing
src/gz openwrt_telephony http://downloads.openwrt.org/releases/1 … /telephony
src/gz gargoyle_pl http://dl.eko.one.pl/gargoyle-pl/openwr … 1/packages
src/gz eko1_base http://dl.eko.one.pl/openwrt-19.07/pack … _24kc/base
src/gz eko1_luci http://dl.eko.one.pl/openwrt-19.07/pack … _24kc/luci
src/gz eko1_packages http://dl.eko.one.pl/openwrt-19.07/pack … c/packages
src/gz eko1_routing http://dl.eko.one.pl/openwrt-19.07/pack … kc/routing
src/gz eko1_telephony http://dl.eko.one.pl/openwrt-19.07/pack … /telephony
src/gz gargoyle_kmods http://dl.eko.one.pl/gargoyle-pl/openwr … s-4.14.172
src/gz gargoyle_base http://dl.eko.one.pl/gargoyle-pl/openwr … _24kc/base

Problem in caps SNAPSHOT 404 not found
this its work https://downloads.openwrt.org/snapshots … 24kc/base/
snapshot

ok thank you for me dont work
opkg update

Downloading package list for eko1_routing source...
Package list for eko1_routing downloaded successfully.

Downloading package list for gargoyle_base source...
Package list for gargoyle_base downloaded successfully.

Downloading package list for eko1_packages source...
Package list for eko1_packages downloaded successfully.

Downloading package list for gargoyle_kmods source...
Package list for gargoyle_kmods downloaded successfully.

Downloading package list for openwrt_telephony source...
Package list for openwrt_telephony downloaded successfully.

Downloading package list for openwrt_luci source...
Package list for openwrt_luci downloaded successfully.

Downloading package list for openwrt_packages source...
Package list for openwrt_packages downloaded successfully.

Downloading package list for openwrt_routing source...
Package list for openwrt_routing downloaded successfully.

Downloading package list for eko1_luci source...
Package list for eko1_luci downloaded successfully.

Downloading package list for gargoyle_pl source...
Package list for gargoyle_pl downloaded successfully.

Downloading package list for openwrt_base source...
Package list for openwrt_base downloaded successfully.

Downloading package list for eko1_telephony source...
Package list for eko1_telephony downloaded successfully.

Downloading package list for eko1_base source...
Package list for eko1_base downloaded successfully.

opkg install f2fs-tools
ERROR: No package named f2fs-tools found, try updating your package lists
write this error

And is true this is proper name. snapshot is not 19.07-SNAPSHOT! but gargoyle 1.13.0.0pre3 (93de94dd) opkg.conf ist all SNAPSHOT