You can modify this code
.data
msg1: .asciiz "Enter the first number: "
msg2: .asciiz "\nEnter the second number: "
result: .asciiz "\nThe result of addition is: "
.text
li $v0,4
la $a0,msg1
syscall
li $v0,5
syscall
move $t1,$v0
li $v0,4
la $a0,msg2
syscall
li $v0,5
syscall
move $t2,$v0
Add $t3,$t1,$t2
li $v0,4
la $a0,msg3
syscall
li $v0,1
move $a0,$t3
syscall
li $v0,10
syscall