I assume you’re proposing to install a washing machine and possibly a clothes dryer within the existing kitchen of the Unit that you are proposing to purchase.
If that’s the case, and as those works will likely require the placement of waterproofing material on the existing floor (below the washing machine in accordance with Building Codes) and will certainly involve alterations to the services of the Unit, and specifically to the electricity, water supply, and drainage, then YES you will need to seek and obtain the prior written consent of the Owners Corporation (O/C).
If your proposed works will involve physical changes, alterations, or additions to the Common Property (e.g. the floor) the those will need to be considered at a General Meeting of the O/C and be agreed to by ≥75% of those in attendance, and otherwise, you will need to provide the O/C with written notice of your intentions (e.g. to only make plumbing/drainage alterations) a minimum 14 days in advance whereupon the O/C may impose conditions that are usually limited to the use (by you) of licensed tradespeople and to the interruption of services to others (e.g. neighbours).
As you’re still contemplating your purchase, why not contact the Strata Manager and/or the Executive Committee Secretary on a formal basis and seek their advice and if possible an agreement in principle to your proposed works; you never know, an existing Owner may have already made a similar installation?