Sure, let's use a Feistel cipher with two rounds and a Caesar cipher as the function $\backslash ($F$\backslash )$ for encryption and decryption. The key values for the Caesar cipher are given as $\backslash ($K$1=1\backslash )$ and $\backslash ($K$2=3\backslash ).$

$**$Encryption:$**$

$1.**$Initial Permutation:$**$

$-$ Split the plaintext "BRUCELEE" into two halves: "BRU" and "CELEE."

$2.**$Round $1$:$**$

$-$ Left half: "BRU"

$-$ Right half: "CELEE"

$-$ Apply the Caesar cipher function with $\backslash ($K$1=1\backslash )$ to the right half: $"$DFMFFFB$"$

$-$ XOR the result with the left half: "BRU XOR DFMFFFB$"($perform XOR operation character by character$)$

$-$ Result: "ACSJBID"

$3.**$Round $2$:$**$

$-$ Left half: $"$CE$"$

$-$ Right half: "ACSJBID"

$-$ Apply the Caesar cipher function with $\backslash ($K$2=3\backslash )$ to the right half: $"$DFVQGNG$"$

$-$ XOR with the left half: $"$CE XOR DFVQGNG$"$

$-$ Result: "HWXELYD"

$4.**$Final Permutation:$**$

$-$ Concatenate the results from the last round: "HWXELYD"

So$,$ the encrypted ciphertext for "BRUCELEE" using the specified Feistel cipher with two rounds and Caesar cipher as the function is "HWXELYD."

$**$Decryption:$**$

To decrypt, we reverse the process:

$1.**$Initial Permutation:$**$

$-$ Split the ciphertext "HWXELYD" into two halves: $"$HWX$"$ and "ELYD."

$2.**$Round $2($in reverse order$)$:$**$

$-$ Left half: "ELYD"

$-$ Right half: $"$HWX$"$

$-$ Apply the inverse of the Caesar cipher function with $\backslash ($K$2=3\backslash )$ to the left half: "CZUAZAX"

$-$ XOR with the right half: "ELYD XOR CZUAZAX"

$-$ Result: "CELEE"

$3.**$Round $1($in reverse order$)$:$**$

$-$ Left half: $"$HWX$"$

$-$ Right half: "CELEE"

$-$ Apply the inverse of the Caesar cipher function with $\backslash ($K$1=1\backslash )$ to the left half: $"$GVKDDDC$"$

$-$ XOR with the right half: $"$HWX XOR GVKDDDC$"$

$-$ Result: "BRUCEE"

$4.**$Final Permutation:$**$

$-$ Concatenate the results from the last round: "BRUCEE"

So$,$ decrypting "HWXELYD" yields the original plaintext "BRUCEE."