Yes, Tesla vehicles (including the Model Y) enable you to be able set the maximum charging amperage from the charging menu. Unless you are having difficulty charging, i.e the circuit breaker for the outlet you are using keeps tripping off there is no need to set the charging amperage. Normally the Tesla vehicle and the EVSE establish the voltage (120V or 240) and the maximum charging amperage that can be supported automatically within the first 30 seconds of plugging in the vehicle.
I suggest writing down your questions for the electrician. The more you know the better informed you will be when making any purchase as relates to charging your Model Y at home.
Every new Tesla vehicle comes with a Tesla Mobile Connector (Tesla's portable EVSE.) The Mobile Connector may be all you need to get started charging your Tesla at home. The Mobile Connector comes with a NEMA 5-15 power plug adapter that will plug into any standard outlet. You can purchase additional power plug adapters for the Mobile Connector from the Tesla Store. The total length of the power plug adapter, Mobile Connector unit and the charging cord is ~20ft. It may be too short to reach your vehicle unless you use an extension cord. Tesla does not recommend using an extension cord with the Mobile Connector. For short term use, if nothing else will do, people do use quality extension cords with the Mobile Connector. The extension cord should be as short as possible, 10 or 12 gauge with a proper ground plug and receptacle. You would need to keep the extension cord connection dry (there are interconnect covers sold for this purpose.) You should also keep the Mobile Connector off the ground, dry. When plugged into a receptacle the Mobile Connector electronics unit should be supported, not left to hang from the power plug. If you plan to use an existing 120V receptacle (either 15 amp or 20 amp) if it is more than 5 years old replace it before you start charging. Old, corroded worn out receptacles should be replaced before you attempt to charge an EV from that outlet. Replace with a contractor grade or a hospital grade receptacle. The receptacles displayed loose in bins by the big box stores are suitable for plugging in a table lamp, spend a few $ for a quality receptacle. You may only need to use the Mobile Connector to charge your vehicle at 120V for a short time, until the electrician can schedule and complete the work once you decide on your long term charging setup. The Mobile Connector is not all-weather rated, continued exposure of the Mobile Connector to rain and dampness will shorten the life of the Mobile Connector.