The bootloader must load the DTBO image that is compatible with the recovery image. in your case Touch is not working because the TWRP version does not support it. There is not much you can do, the TWRP kernel must be compiled with touch support (or maybe binary hex-patched).
Look for dtbo.img or (edit: dtb is appended to kernel for y7)
use the adb shell commands TWRP comes with:
You can also try to boot TWRP from fastboot instead of flashing it, sometimes this will affect to touch screen work.
fastboot boot C:\adb\TWRP_3.2.2_TRT-LX1_by_kiruha_21.img
regarding switch slots, you can not switch if you don't have A/B device. don't mix up different recoveries.
please note the differences between /etc/recovery.fstab
only in TWRP_3.2.2_TRT-LX1_by_kiruha_21
/dev/block/bootdevice/by-name/userdata fs: f2fs
vendor, product, version, log
only in TWRP_3.2.2_TREBLE_TRT-LX1_by_kiruha_21
/dev/block/bootdevice/by-name/userdata fs: ext4
fsc, lksecapp, sbl1, dip, dpo, limits, mcfg, mdtp, mota, oem, syscfg
Please check if your phone has f2fs or ext4 file system, and check if vendor partition is present or not. Select the proper TWRP variant according to your partition layout.
you can check your partitions from adb shell or terminal emulator (one of these commands will work)
ls -d /dev/block/*/*/*/by-name/*
ls -d /dev/block/*/*/by-name/*
ls -d /dev/block/*/by-name/*
for file system type (one of these commands will work)
df -t ext4 /data
df -t f2fs /data
df -T /data
mount | grep "/data "