process error repeatly after downgrade form miui 10 to 9

[msd_m]

hi
i don't like miui 10 because of battery draining thus downgraded to miui 9.5 . after downgrading i getting repeatly error say "unfortunately, android process stopped" and i cant do any thing. how can i fix it. please help. error screenshot attached.
thanks

 

[ingbrzy]

wipe wipe wipe

 

[msd_m]

wipe wipe wipe

ok. thanks

 

[msd_m]

wipe wipe wipe

before wiping, how can i backup my installed apps?

 

[msd_m]

before wiping, how can i backup my installed apps?

i found it, done with miui backup but not all apps.