Use static scraping libraries and make same network calls which the website makes internally (passing same query params and request headers).
curl --location --request GET 'https://www.91mobiles.com/template/category_finder/finder_ajax.php?show_next=1&ord=0.17428677812670812&excludeId=&hash=&search=&hidFrmSubFlag=1&page=1&category=mobile&unique_sort=ga_views&gaCategory=Upcoming+Mobiles+Price+List+in+India-filter&requestType=1&showPagination=1&listType=list&listType_v3=list&listType_v1=list&listType_v2=list&listType_v4=list&listType_v5=list&listType_v6=list&page_type=upcoming&finderRuleUrl=&selMobSort=ga_views&hdnCategory=mobile&user_search=&url_feat_rule=upcoming-mobiles-in-india&buygaCat=upcoming-mob&amount=0%3B200000&sCatName=mobile&price_range_apply=1&tr_fl%5B%5D=mob_market_status_filter.marketstatus_filter%3Aupcoming&tr_fl%5B%5D=mob_market_status_filter.marketstatus_filter%3Arumoured' \
--header 'x-requested-with: XMLHttpRequest' \
--header 'user-agent: Mozilla/5.0'