Hi,
Shame the photo has "kiss-buy" plastered over the last letters/digits of the part number.
A cursory glance at the website for the purchase, no idea what a BMS is (in a sense), no datasheet to look at, the picture on the device of n batteries in series, the above remark that 24V isn't enough to begin with, let alone adding current regulation... I'm no expert, so I wonder if paralleling batteries for a series device makes any difference? Do you put sense wires on each battery with that, or one at the top and another at the bottom? The times I've pondered sensing current regulation in parallel LED strings, using one sensing device - I've always desisted as it seems a "might get away with it, or possibly won't" method...
Maybe that device is fine, if you can get a higher voltage version, but for that price, or maybe a little more, you can buy a plug-in smps and a battery charger/monitor IC + few components that I'm pretty certain will cover the design you wish to implement, with the advantage of design tools, app notes, and, I'll bet, adaptable reference designs.
To limit current, ignoring what Klaus has pointed out, you'd need a constant current source circuit to keep it to 2A, and evidently the discharge one also, unless you can know everything in advance that may ever happen
. How - look for current limiting designs, from two BJTs (not the best method), to current sense amplifier + switch type device or op amp and mosfet/BJT current source/sink, then there are ICs that do all that.
I also recommend the (ubiquitous) fuses as protection in relevant places.
Probably there are other methods.
No idea of prices, by doing a bit of research you may find an equally-priced/ reasonably priced evaluation board for battery charging ICs that comes with plenty of documentation for what you intend, and is customisable, rather than something not so well documented from an online seller - see if you can get more info. from the seller about the BMS, anyway.