Not just any laptop, it would have to have at least 8GB of memory if it is running Windows and you ever plan on using it for miscellaneous stuff, because you need Bitcoin Core to run Bisq, and Core itself uses 2GB, and then Bisq consumes another 1GB at most. If neither of the above are true, then you might get away with 4GB of memory.
I am sure it can run just fine with even below 8GB of memory (I don't know anyone who runs less in 2022) because you are not keeping it open and running all the time, but you can also reduce memory usage following instructions on their website.Combine that with closing all other applications you are not using and shutting down other processes, you will be just fine.
However, it's always good to upgrade RAM and if you are running older laptop with DDR3 or DDR4, than used RAM is very cheap.
https://bisq.wiki/Reducing_memory_usage
My old Raspberry power supply won't turn on anymore.. Experiments delayed.
RIP power supply? 