What are some free and lightweight blockchain platforms to build apps?

Hello indie hackers,
I'm a newbie to blockchain and now I'm looking for some free blockchain platforms to store data (like a database but there is no update or delete data function). I searched for this a lot on Google but most of them are hard to install (some are required to install a full-node / too many dependencies / some are limited on specific OS / ...). I will appreciate it so much if you could recommend me some blockchain platforms which satisfy my conditions. Thank you !!!