PlayerMove2D

using UnityEngine;

public class PlayerMove2D : MonoBehaviour {

    public float moveSpeed = 5f;
    public float jumpPower = 5f;
    public int jumpsLimit = 2;

    Rigidbody2D _rigidbody;
    int _jumpsDone;
    float _horizontalInput;
    bool _wantToJump;

    private void Start() {
        _rigidbody = GetComponent<Rigidbody2D>();
    }

    private void Update() {
        _horizontalInput = Input.GetAxis("Horizontal") * moveSpeed; // -1 .. 1

        if (Input.GetButtonDown("Jump")) {
            _wantToJump = true;
        }

        if (_horizontalInput > 0) {
            transform.localEulerAngles = new Vector3(0f, 0f, 0f);
        } else if (_horizontalInput < 0) {
            transform.localEulerAngles = new Vector3(0f, 180f, 0f);
        }
    }

    private void FixedUpdate() { // 0.02
        if (_wantToJump && _jumpsDone < jumpsLimit) { // true/false
            _rigidbody.velocity = new Vector2(_horizontalInput, jumpPower);
            _jumpsDone++;

        } else {
            _rigidbody.velocity = new Vector2(_horizontalInput, _rigidbody.velocity.y);
        }

        _wantToJump = false;
    }

    private void OnCollisionEnter2D(Collision2D collision) {
        _jumpsDone = 0;
    }
}