When someone hosts or feeds you, pray for them. The Prophet ﷺ ate at Saʿd ibn ʿUbādah's and said: “May the fasting break their fast with you, may the righteous eat your food, and may the angels send ṣalāh upon you.” (Abū Dāwūd — ṣaḥīḥ). He also said: “Allāhumma bārik lahum fīmā razaqtahum, waghfir lahum warḥamhum.” (Muslim).
العربية: عن أنس رضي الله عنه أنّ النبيّ ﷺ أفطر عند سعد بن عبادة فقال: «أفطر عندكم الصائمون، وأكل طعامكم الأبرار، وصلّت عليكم الملائكة». (أبو داود).
After a meal at someone's home, make duʿā for them — ‘Allāhumma bārik lahum…’