Here's a Python program that reads multiple lines of plain text from the user and counts the occurrences of each word. The words are listed in alphabetical order.

# Initialize a dictionary to store word counts

word$\_$counts $=\{\}$

# Read multiple lines of input from the user until an empty line is entered

while True:

line $=$ input$("$Enter line: $")$

if line $==""$:

break

# Split the line into words

words $=$ line.split$()$

# Update the word counts

for word in words:

if word in word$\_$counts:

word$\_$counts$[$word$]+=1$

else:

word$\_$counts$[$word$]=1$

# Get the words in alphabetical order

sorted$\_$words $=$ sorted$($word$\_$counts.keys$())$

# Print the word counts in alphabetical order

for word in sorted$\_$words:

print$($f$"\{$word$\}\{$word$\_$counts$[$word$]\}")$

$1$st step:

A dictionary word$\_$counts is initialized to store the count of each word.

A while loop is used to read multiple lines of input until an empty line is entered.

Each line is split into words using split$().$

For each word in the line, the count is updated in the word$\_$counts dictionary.

After all input lines are processed, the words are sorted alphabetically using sorted$().$

The sorted words and their counts are printed.