How to specify certain labels on matplotlib legend

Question

I try to produce the following plot, but the legend doesn't look very good. I want years to be integer number (not decimals) and space in periods like 2000, 2005, 2010, 2015, 2020 in the colorbar. Also legend title "Years" should be on top of the legend (not in the middle color bar) with fontsize=14. Hope someone can help.

import pandas as pd
import random
import matplotlib.pyplot as plt
df=pd.read_csv(r"https://raw.githubusercontent.com/tuyenhavan/Course_Data/main/data.csv")
years=[i for i in range(2000,2022)]
df["Year"]=[random.choice(years) for i in range(len(df))]
fig, ax=plt.subplots(figsize=(15,8))
point=plt.scatter(df.Extent_km2/1000, df.Resolution_m, c=df.Year)
plt.xticks(fontsize=13) 
plt.yticks(fontsize=13)
ax.set_xlabel(r"Spatial extent (1000 $\rmkm^2$)", fontsize=15)
ax.set_ylabel("Spatial resolution (m)", fontsize=15) 
fig.colorbar(point)
plt.show()