Brown bear, brown bear, what do you see?
I see a red bird looking at me.
啡色忍受熊 啡色忍受熊 你見到乜嘢？
fe1sik1 jan5 sau6 hung4 , fe1sik1 jan5 sau6 hung4, nei5 gin3 dou3 mat1 je5?
我見到一隻紅色雀睇著我
Ngo5 gin3 dou3 jat1 zek3 hung4 sik1 zoek1 tai2 zyu3 ngo5

色 sik1=color ✅it always be reduce when it was with a noun.
For example, Will you say "There is a yellow color duck." ?
It's Okay ,but it will become a bit burden.
Same in Cantonese.

忍受 jan5 sau6=endure 
啡熊 fe1 hung4=brown bear🐻

見gin3 =see ✅ but we usually add 到dou3 behind it .
睇tai2=look 著zyu3=ing add 著zyu3 behind a verb can stress that it is processing. This can also be applied to the word 見。
BTW many people in Hong Kong read zyu3 as zyu6 .its wrong.😫

Same as other paragraphs.

Red bird, red bird, what do you see?
I see a yellow duck looking at me.
紅色雀, 紅色雀, 你見乜嘢
Hung4 sik1 zeok1, hung4 sik1 zeok1, nei5 gin3 mat1 je5?
我見一隻黃色鴨睇我
Ngo5 gin3 jat1 zek3 wong4 sik1 aap3 tai2 ngo5

Yellow duck, yellow duck, what do you see?
I see a blue horse looking at me.
黃色鴨, 黃色鴨, 你見 乜嘢
Wong4 sik1 aap3, wong4 sik1 aap3, nei5 gin3 mat1 je5?
我見一隻藍色馬睇我
Ngo5 gin3 jat1 zek3 laam4 sik1 maa5 tai2 ngo5

Blue horse, blue horse, what do you see?
I see a green frog looking at me.
藍色馬, 藍色馬, 你見 乜嘢
laam4 sik1 maa5, laam4 sik1 maa5, nei5 gin3 mat1 je5?
我見一隻綠色青蛙睇我
Ngo5 gin3 jat1 zek3 lok6 sik1 cing1 waa1 tai2 ngo5

Green frog, green frog, what do you see?
I see a purple cat looking at me.
綠色青蛙, 綠色青蛙, 你見 乜嘢
lok6 sik1 cing1 waa1, lok6 sik1 cing1 waa1, nei5 gin3 mat1 je5?
我見一隻紫色貓睇我
Ngo5 gin3 jat1 zek3 zi2 sik1 maau1 tai2 ngo5

Goldfish, goldfish, what do you see?
I see a teacher looking at me.
金色魚, 金色魚, 你見 乜嘢
gam1 sik1 jyu2, gam1 sik1 jyu2, nei5 gin3 mat1 je5?
我見一個先生睇我
Ngo5 gin3 jat1 go3 sin1 saang1 tai2 ngo5

Teacher, teacher, what do you see?
I see children looking at me.
先生, 先生你見 乜嘢
Sin1 saang1, sin1 saang1, nei5 gin3 mat1 je5?
我見啲細路睇我
Ngo5 gin3 di1 sai3 lou6 tai2 ngo5

Children, children, what do you see?
We see a brown bear, a red bird, a yellow duck, a blue horse, a green frog, a purple cat, a white dog, a black sheep, a goldfish, and a teacher looking at us.
細路, 細路, 你見 乜嘢
Sai3 lou6, sai3 lou6, nei5 gin3 mat1 je5?
我哋見一隻啡色忍受, 一隻 紅色雀, 一隻黃色鴨, 一隻藍色馬, 一隻綠色青蛙, 一隻紫色貓, 一隻白色狗, 一隻黑色綿羊, 一隻金色魚, 一個先生, 睇我
Ngo5 dei6 gin3 jat1 zek3 fe1 sik1 jan5 sau6, jat1 zek3 zoek1, jat1 zek3 Wong4 sik1 aap3, jat1 zek1 laam4 sik1 maa5, jat1 zek3 lok6 sik1 cing1 waa1, jat1 zek3 zi2 sik1 maau1, jat1 zek3 baak6 sik1 gau2, jat1 zek3 hak1 sik1 min4 joeng2, jat1 zek3 gam1 sik1 jyu2, jat1 go3 sin1 saang1, tai2 ngo5

That’s what we see.
嗰個 我哋 見
呢啲就係我哋見到嘅
Go2 go3 ngo5 dei6 gin3
ne1 di1 zau6 hai6 ngo5 dei2 gin3 dou3 ge3

啡色忍受 Brown Bear - Converting a children's story to Cantonese

To put it a bit more elegantly and rhythm you can use the following,

brown bear = 啡熊

red bird = 赤鳥/紅雀

blue horse = 青馬.  You can leave out "色".  Here 青 means blue

As for 青蛙 & 金魚, you don't need to prefix any more additional color description.  They are already green and gold.  Whether you need to add 色 or not depends on what rhythm you wants to use or to change the pace.  You can use 望 instead of 見

Brown bear, brown bear, what do you see?
I see a red bird looking at me.
啡色忍受, 啡色忍受 你見 乜嘢
fe1 sik1 jan5 sau6, fe1 sik jan5 sau6, nei5 gin3 mat1 je5?
我見一隻紅色雀睇我
Ngo5 gin3 jat1 zek3 hung4 sik1 zoek1 tai2 ngo5

Red bird, red bird, what do you see?
I see a yellow duck looking at me.
紅色雀, 紅色雀, 你見 乜嘢
Hung4 sik1 zeok1, hung4 sik1 zeok1, nei5 gin3 mat1 je5?
我見一隻黃色鴨睇我
Ngo5 gin3 jat1 zek3 wong4 sik1 aap3 tai2 ngo5

Yellow duck, yellow duck, what do you see?
I see a blue horse looking at me.
黃色鴨, 黃色鴨, 你見 乜嘢
Wong4 sik1 aap3, wong4 sik1 aap3, nei5 gin3 mat1 je5?
我見一隻藍色馬睇我
Ngo5 gin3 jat1 zek3 laam4 sik1 maa5 tai2 ngo5

Blue horse, blue horse, what do you see?
I see a green frog looking at me.
藍色馬, 藍色馬, 你見 乜嘢
laam4 sik1 maa5, laam4 sik1 maa5, nei5 gin3 mat1 je5?
我見一隻綠色青蛙睇我
Ngo5 gin3 jat1 zek3 lok6 sik1 cing1 waa1 tai2 ngo5

Green frog, green frog, what do you see?
I see a purple cat looking at me.
綠色青蛙, 綠色青蛙, 你見 乜嘢
lok6 sik1 cing1 waa1, lok6 sik1 cing1 waa1, nei5 gin3 mat1 je5?
我見一隻紫色貓睇我
Ngo5 gin3 jat1 zek3 zi2 sik1 maau1 tai2 ngo5

Goldfish, goldfish, what do you see?
I see a teacher looking at me.
金色魚, 金色魚, 你見 乜嘢
gam1 sik1 jyu2, gam1 sik1 jyu2, nei5 gin3 mat1 je5?
我見一個先生睇我
Ngo5 gin3 jat1 go3 sin1 saang1 tai2 ngo5

Teacher, teacher, what do you see?
I see children looking at me.
先生, 先生你見 乜嘢
Sin1 saang1, sin1 saang1, nei5 gin3 mat1 je5?
我見啲細路[哥]睇我  Again the addition of 哥 is to change the rhythm
Ngo5 gin3 di1 sai3 lou6 tai2 ngo5

Children, children, what do you see?
We see a brown bear, a red bird, a yellow duck, a blue horse, a green frog, a purple cat, a white dog, a black sheep, a goldfish, and a teacher looking at us.
細路, 細路, 你見 乜嘢
Sai3 lou6, sai3 lou6, nei5 gin3 mat1 je5?
我哋見一隻啡色忍受, 一隻 紅色雀, 一隻黃色鴨, 一隻藍色馬, 一隻綠色青蛙, 一隻紫色貓, 一隻白色狗, 一隻黑色綿羊, 一隻金色魚, 一個先生, 睇我
Ngo5 dei6 gin3 jat1 zek3 fe1 sik1 jan5 sau6, jat1 zek3 zoek1, jat1 zek3 Wong4 sik1 aap3, jat1 zek1 laam4 sik1 maa5, jat1 zek3 lok6 sik1 cing1 waa1, jat1 zek3 zi2 sik1 maau1, jat1 zek3 baak6 sik1 gau2, jat1 zek3 hak1 sik1 min4 joeng2, jat1 zek3 gam1 sik1 jyu2, jat1 go3 sin1 saang1, tai2 ngo5

That’s what we see.
嗰個 我哋 見
Go2 go3 ngo5 dei6 gin3