Use RTD to backfill/download intra data, if you need data for a few scrips
And if need data for more scrips, then only alternative, go for paid service and you will get data on daily basis.
Here is code snippet in Python for getting 1minute data for 1 day.
get_quote_data(symbol='SBIN.NS', data_range='1d', data_interval='1m'):
res = requests.get('https://query1.finance.yahoo.com/v8/finance/chart/{symbol}?range={data_range}&interval={data_interval}'.format(**locals()))
data = res.json()