I have seen adapters to convert some rear wheels to disc brake:
ADEDS 6 Bolt Bicycle Freewheel Threaded Hubs Disk Bike Disc Brake Rotor Flange Adapter (44mm)
https://www.amazon.com/dp/B01JREIQYG/ref=cm_sw_r_cp_apa_i_75ryEbJZV9NPA
And the frame adapter:
Fashion Life Adjustable Bike Disc Brake Bracket Mounting Holder New Bicycle MTB
https://www.amazon.com/dp/B019OML8VE/ref=cm_sw_r_cp_apa_i_U1ryEb6MT919S
The frame adapter can work on a front standard fork, but not suspension fork. I have no idea of the quality and stability of the adapters. As far as I know you would have to get a new front wheel, with hub designed for disc brakes. Another option is to get hydraulic rim brakes, with dual compound - high speed shoes.