What I wanted to say is that Android handles RAM by itself and there is not much you can do about that. This also means that 100 MB free on start up is not necessarily a bad thing.
I see however that being only able to have one app active is annoying and might be a problem.
I am not an Android developer so I don’t want to give you false hopes, but we would need much more information to help you. Asking for the option to free RAM might hint that we are dealing with an xy problem.
So, what device are you running, which version of LineageOS, what apps are you running? Have you already tried to disable the apps battery optimization etc.
What I wanted to say is that Android handles RAM by itself and there is not much you can do about that. This also means that 100 MB free on start up is not necessarily a bad thing.
I see however that being only able to have one app active is annoying and might be a problem.
I am not an Android developer so I don’t want to give you false hopes, but we would need much more information to help you. Asking for the option to free RAM might hint that we are dealing with an xy problem.
So, what device are you running, which version of LineageOS, what apps are you running? Have you already tried to disable the apps battery optimization etc.