Peeling paint in bathroom

[Goodmum1234]

After plastering a few years ago a tenant painted straight onto the walls without a watery coat, it has been peeling since.
I'm useless at decorating but think I need to sandpaper it all off, then paint in a watery paint and then a few coats of a good quality bathroom paint.
Am
Am I on the right lines?
Thanks in advance

We did 2 'mist' coats on all our plastered walls. Do u have good ventilation in the bathroom? It may not have been helped by steam from a shower/bath.

Removing the peeling paint and redoing is the way to go. Not sure mist coating will be necessary as the plaster should be dry by now. However, it won't hurt.

Removing the peeling paint and redoing is the way to go. Not sure mist coating will be necessary as the plaster should be dry by now. However, it won't hurt.

Thank you both. Yes there's a good fan. Some of the paint might not sand off though so I'm worried there will be bumps when painted unless I scrape. What do you think?