Recent studies reveal widespread concern and increasing lack of understanding about how personal data is collected, shared, and used online without consent. This issue is compounded by limited options available for digital citizens to understand, control and manage their data flows across platforms, underscoring the need to explore how this lack of trust and transparency affects citizens' data practices including their capacities to act in a modern knowledge society. Despite the promising research within this field, important demographics are often overlooked, particularly people from marginalized social groups such as elderly, socially and economically challenged communities, and younger participants. This paper addresses this gap by specifically focusing on these underrepresented groups, emphasizing the need for exploring their understandings and percepts of online data practices. Drawing on three semi-structured focus group interviews, the paper asks: to what extent can public attitudes and concerns about data sharing on the internet inform the potential strategies and frameworks necessary to enhance digital trust and democratic data agency particularly among marginalized groups in Denmark? The study explores the types of information, levels of transparency, and agency people desire in their daily online data practices. Additionally, it explores how these insights can potentially inform the future development of fair data strategies and technological approaches to enhance digital trust and democratic data agency. Key findings point out the need for transparent, accessible privacy policies and data management tools, emphasizing that transparency alone is insufficient without enhancing democratic agency to address trust issues and foster a more inclusive digital environment. Keywords: public understanding, personal data, digital trust, data practices, data agency