Iterating bash commands inside docker container - bash

Question

I am a beginner to Docker and was trying to optimize the following bash shell code. The below code continuously has to create a docker container and remove it. What I would like is a one-time creation of the docker container; then based on the if-else condition, the corresponding command gets iteratively executed in while loop and finally, the docker container gets deleted. I have tried to play around with docker entrypoint commands but all of them seem to insist on a single line command with docker run. Some help will be deeply appreciated! Thanks!
#!/bin/bash
FILE=$1
flag=1
while read line; do
#echo $line
#echo $flag
if [ $flag -gt 0 ] && [ $flag -lt 23189 ]; then
docker run --rm -v $(pwd):/eric -w /eric --entrypoint /bin/sh fedora -c "dnf info $line | tee -a manifest-fed:Core.txt; dnf repoquery --srpm $line"
((++flag))
elif [ $flag -gt 23188 ] && [ $flag -lt 46379 ]; then
docker run --rm -v $(pwd):/eric -w /eric --entrypoint /bin/sh fedora -c "dnf info $line | tee -a manifest-fed:Old.txt; dnf info $line"
((++flag))
elif [ $flag -gt 46378 ] && [ $flag -lt 69571 ]; then
docker run --rm -v $(pwd):/eric -w /eric --entrypoint /bin/sh fedora -c "dnf info $line | tee -a manifest-fed:Graphics.txt"
((++flag))
fi
done<"$1"

Answer 1

Create container in detached mode:
docker run -d -t --rm --name my_container -v $(pwd):/eric -w /eric fedora
Run your commands in this container:
docker exec my_container sh -c "echo test"

Answer 2

You may wrap those commands in a single script and put it in your pwd mapped to '/eric' volume. And then execute them something like:
docker run --rm -v $(pwd):/eric -w /eric --entrypoint /bin/sh fedora -c "/eric/dnf-info.sh 1 '$line'"
Script dnf-info.sh may be:
#! /bin/sh
case $1 in
1)
dnf info "$2" | tee -a manifest-fed:Core.txt; dnf repoquery --srpm "$2"
;;
2)
dnf info "$2" | tee -a manifest-fed:Old.txt; dnf info "$2"
;;
3)
dnf info "$2" | tee -a manifest-fed:Graphics.txt
;;
esac