Resolved questions
When there are two or more consonants in one syllable, what is the rule for pronouncing it?

ไ- is one of 32 vowels in Thai language. The rule of this vowel is ไ + consonant
ex. ไ+กล = ไกล = Glai , ไ+ป = ไป = Bpai.
if any consonant/syllable come before ไ- you have to pronounce it first before ไ-
ex. อะไร = A-rai, สไบ = Sa-bai

there are only 3 alphabets that can be made into double consonant, ร, ล, ว. They have to come after other alphabet and you pronounce both alphabets. for example, ไกล is the vowel ไ- (ai) plus the consonant ก and ล. ก(gor=g) + ล(lor=l) so they become กล(gl) --> ไกล glai. Basically you just kinda say both consonant all at once and apply the same rule as usual

שלים עברים
shalom averim , mashalamkha?

firstly all of above answered are all correct indeed.
i have nothing to add more:

but as i also interested in arabic and hebrew, i found they are some certain alike to thai language,
especially the term of many consenant together without the need of the vowels.

ex:
จรวด ตลก กรม ทรวง กรกต..............
none of these words appear the vowels but indeed there are vowels that had consist in consenant itself, just like in hebrew and arabic.
indeed: there are numbers of these kind of words in thai.
จรวด read as: ja-ruad
ตลก read as : Ta-lod
กรม read as : grom (all together in one sylable)
ทรวง read as: swang (all tother in one sylable)
กรกต read as : go-ra-god

ex:
แถลง read as : Tha-laeng not Thae-long
เฉลิม read as : cha-lerm not chae-lim


Just like the word ไกล that you are puzzle with.
indeed, sometime we the thai also just get used to in, and not really try to think why.