Rongtong Shenzhen Stock Exchange 100 is an index fund. If you want to find an ETF fund in the stock software, you should check it out. Maybe you chose the wrong classification.
Fund companies purchase funds, which is a direct selling channel; Tongda letter subscription fund belongs to the consignment channel. The difference is not big, mainly depends on which purchase rate is cost-effective, usually there should be no difference.
In addition, the stock trading account can also buy ETF and LOF funds, the former belongs to index funds, and the latter belongs to open-end funds that can be traded in the secondary market.