Hi @kouliscon ,
The user needs to press enter after entering the first few matching letters. The example below is on a test list I have, but could be used on any list.

There are only two things to set - the OnChange of the Text box
With(
{
wMatch:
If(
!IsBlank(Self.Text),
LookUp(
YurListName,
StartsWith(
YourFieldName,
Self.Text
)
).YourFieldName
)
},
UpdateContext(
{
varMatch:
If(
!IsBlank(wMatch),
wMatch,
Self.Text
)
}
)
)
and the Default of the Text Box
If(
!IsBlank(varMatch),
varMatch,
Parent.Default
)
NOTE: Parent.Default is only necessary if the box is in a Form as you want to show the existing value once saved. You would also add this to the screen OnVisible and your Save function
UpdateContext({varMatch:Blank()})
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