I do believe that there are the following things that you can try:
1. Reliable Lending services
2. Holding for the long term
But you do need to understand that to do any of this you would be entrusting your coins to a third party service which would not only need a lot of prior research but at the same time there is this possibility of getting scammed.
- find some reliable websites for lending if you really want to
- keep your keys and your Bitcoins with you till the time the price doubles of whatever rate you brought in
*_*
Just with Bitcoin itself you won't see any kind of passive income as Bitcoin wasn't build that way. There are other services such as wallets and lending websites where you can earn passively from there. Bitcoin being the most popular crypto and the most used one has a lot of available services accepting Bitcoin so you won't have any problems finding one. Try looking for Bitbonds and Abra because this is the ones I know personally on what you are trying to look for.
For having small passive income, and also actually helping the network altruistically, if you have the technical ability, why not run a Lightning node to collect routing fees, OR be a market-maker in JoinMarket?
I do believe that would actually need the active involvement of the person himself.