Yes, just speak - and don’t worry!
If they are your real friends, they will respect your efforts to try to speak.
If they are not real friends, ask them to speak Thai with you (since they are real language experts
If they are Thai people, then I’m quite sure that if they have not lived in a native speaking country all their lives, then their English is probably not ”perfect” either
I would say, to this good question we all feel at some point: Learn as much as you can, then jump in ”with both feet into the water”...so a) grow a thick skin (there are plenty of languages any non-constructive critic does not master); and b) thank them sincerely when they correct you (whether they correct you cordially or not)...Cheers,
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