Bash script does not work as expected

UNIX for Beginners Q & A
1

Repeat this text in a file named notes.txt and run the script
Before bash is a good language a blank line appears
Also, the following notes are displayed incorrectly
What is bad?

==================================
Title   : Note 1
==================================
Category: Computer
Date    : 2019-04-28 17:34:19
==================================
BASH is good language
==================================
1
2


'
 while : ; do
 read line1
 read tit
 read line2
 read cat
 read dat
 read line3
 note=""
 while [ "$not" != "==================================" ]; do
  read not
  note="$note
$not"
 done
 read nro1
 read nro2
#=============================================
# note.tmp
#=============================================
 echo "$line1" >note.tmp
 echo "$tit" >>note.tmp
 echo "$line2" >>note.tmp
 echo "$cat" >>note.tmp
 echo "$dat" >>note.tmp
 echo "$line3" >>note.tmp
 echo "$note" >>note.tmp
 echo "$nro1" >>note.tmp
 echo "$nro2" >>note.tmp
 clear
 cat note.tmp
 read -p "Press enter to continue" jj </dev/tty
done <notes.txt
'
2 
note="$note$not\n"
...
echo -ne "$note" >>note.tmp

--- Post updated at 07:32 ---

For what's here infinite "while" ?

--- Post updated at 07:48 ---

read -p "Press enter to continue" jj </dev/tty

there is option -u

read -p "Press enter to continue" -u 1 jj

while :: do
...
done < notes.txt

Totally pointless loop
Then it's better

jj=""
while [ "$jj" != q ]; do
{
...
} < notes.txt
read -p "Press enter to continue" jj
echo "Start over"
sleep 2
done
3

infinite while is because the notes can have 1, 2 or more lines, until find the fourth line with equal signs.
Thank you

4

The following appends even the first line as a new line, so the initial empty string becomes an empty line:

 note=""
 while [ "$not" != "==================================" ]; do
  read not
  note="$note
$not"
 done

You must either branch on a state variable (e.g. $firstrun), or use the "$separator variable" trick as follows:

 note="" sep=""
 while
  read not &&
  [ "$not" != "==================================" ]
 do
  note="$note$sep$not"
  sep="
"
 done

EDIT: I have changed the oder of read and [ ] . Otherwise one must initialize not="" (or it might have the value from a previous cycle).