Show the number of it how it is showed in the diagram

let's number the carbons for the structure you provided.

The carbon chain is numbered starting from the carbon atom of the carboxylic acid group ($\text{-COOH}$), which is always designated as carbon number 1.

Here's the structure with the carbon atoms numbered:

$$\text{CH}_3\text{-CH(F)-C(OH)(CH}_3\text{)-CH}_2\text{-CH(Br)-CH}_2\text{-COOH}$$

Numbering the carbons from right to left (starting with the $\text{-COOH}$ carbon):

$$\text{C7H}_3\text{-C6H(F)-C5(OH)(CH}_3\text{)-C4H}_2\text{-C3H(Br)-C2H}_2\text{-C1OOH}$$

• C1: The carbon of the carboxylic acid group ($\text{-COOH}$).
• C2: The carbon adjacent to C1.
• C3: The carbon with the bromo ($\text{-Br}$) substituent.
• C4: The carbon between C3 and C5.
• C5: The carbon with the hydroxy ($\text{-OH}$) and methyl ($\text{-CH}_3$) substituents.
• C6: The carbon with the fluoro ($\text{-F}$) substituent.
• C7: The terminal methyl group.