Install certificate and replace all certificate subdomains with domain's one.

install_certificate.sh

#!/bin/sh
DOMAIN_NAME=""
CERTIFICATE_PATH="/etc/letsencrypt/live"
# MAKE SURE USE \ TO PREVENT TRAILING SPACES.
PRIVATE_KEY=""
PUBLIC_CERT=""

rm -rfv "$CERTIFICATE_PATH/$DOMAIN_NAME"
mkdir -pv "$CERTIFICATE_PATH/$DOMAIN_NAME"
echo "$PUBLIC_CERT" | sudo tee -a "$CERTIFICATE_PATH/$DOMAIN_NAME/fullchain.pem"
echo "$PRIVATE_KEY" | sudo tee -a "$CERTIFICATE_PATH/$DOMAIN_NAME/privkey.pem"

# SBD = Subdomain
for SBDFOLDER in $CERTIFICATE_PATH/*$DOMAIN_NAME; do
    if [ ! -d $dir ]; then
        echo "skipped $SBDFOLDER"
        continue
    fi
    
    echo "installing $SBDFOLDER"
    cp -rv "$CERTIFICATE_PATH/$DOMAIN_NAME/." "$SBDFOLDER"
done