You should read your old posts(1 month old):
viewtopic.php?f=28&t=12253For cryptography would require to know math, also there are some math concepts that you didn't learned in school yet. So I'm gonna give you a quick introduction.
Symmetric Encryption:Substitution cipherSubstitution(replacement) is the simplest method for encryption. The Idea is very simple it substitue each letter with another letter from the alphabet.
Example:
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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Z I R A J S B K T C L U D M V E N W F O X G P Y H Q
Attacks:
 Brute Force: A brute force attack checks for every substituted alphabet possible, also known as Exhaustive key search.
https://en.wikipedia.org/wiki/Bruteforce_attack  Letter Frequency Analysis:
https://en.wikipedia.org/wiki/Frequency_analysis
Shift Cipher (or Caesar Cipher)This cypher is a substitution cipher with a simple mathematical description, shifts the plaintext letter by a number of positions in the same alphabet.
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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
P = Plaint text, C = Cyphertext, i = index of the element, k = key
Encryption: Ci = (Pi + k) mod 26
Decryption: Pi = (Ci k) mod 26
Improvement to Caesar Cipher:

Affine SipherThis cypher adds a multiplication of the shift cypher with another part of the key.
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k  key composed of a, b,
Encryption: Ci = (a* Pi + b) mod 26
Decryption: Pi = ((Ci b)/a) mod 26
Attacks:
Since it is a very simple substitution algorithm, this cipher has 2 attacks( Brute Force Attack, and Letter Frequency Analysis)
Stream CiphersA stream cypher encrypts the bits individually(the key is generated, using a key stream generator), look into bitwise operations. Can be broken using Linear cryptanalysi.
Read about:
 Pseudorandom Number Generators (PRNG)
 True Random Number Generators (TRNG)
 Cryptographically Secure Pseudorandom Number Generators (CSPRNG)
 OneTimePad
Block Ciphers Definition:
A block cypher encrypts an entire block of plain text bits at a time with the same key.
DES (Data Encryption Standard) Not gonna write a description on DES already wrote on my previous post, or google for more details.
Attacks:
 Brute Force:
 The key space is too small , so it can be attacked by using brute force  Analytical Attacks
 Differential cryptanalysis
 Linear cryptanalysis