"vaali" kya hai?

Main ek doodh vaali chai lena pasand karunga, dhanyavaad. (In this sentence, does Vaali mean cup?)

Vaala/vaali is a useful word to know. It gives doodh the quality of an adjective. Doodhvaali chai = milky tea (tea with milk). Vaala is used a lot in Hindi conversation. Chaiwala is a seller of tea. Dhobiwala is a washerman. Delhiwala is a person from Delhi. So if you asked someone if they would like a cup of tea and they replied yes and added chiniwali it would mean tea with sugar or sugared tea. The ending will either be e, a or e depending on gender and plurality. I'm sure someone could write a whole book on its use! "Doodhwala" also means a milkman or one who sells milk! If the milkman happened to be a woman it would be Doodhwali.

vali means about asking about getting something i think

Namaste, -वाला(vaalaa),-वाली(vaalee),- वाले(vaale) - suffix. Go with noun, adverb and verb. You don’t find suffix by itself. The 3 examples below are from the lessions. 1. हमारे पास यहवाली अभाग्यवश सिर्फ़ छत्तीस माप में है । Humare paas yehvaali abhagyavach sirf chattis maap mein hai. Unfortunately, we only have this one left, in size 36. यहवाली yehvaali = this one. 2. मैं एक दूधवाली चाय लेना पसंद करूँगा , धन्यवाद । Main ek doodhvaali chai lena pasand karunga, dhanyavaad. I’d like a cup of tea with milk, thanks. दूधवाली - doodhvaali - milky – also could mean a milkwoman. 3. वे लम्बे बालोंवली मेरी चाचीजी है । Weh lambe baalonvaali meri chachiji hai. The long-haired woman is my aunt. Weh lambe baalonvaali- The long-haired one. Here is another example of vaale: सब कुछ ऊपरवाले के हाथ में है। Sab kuch uuparvaale ke hath me hai. Everything is in God’s hand(s). Uuparvaale meaning ‘ the one up there’=God. घर ghar house + suffix vaalaa or vaali घरवाला – gharvaalaa - master or owner of a house. घरवाली – gharvaali(ee)- wife. Good luck in your learning Hindi! Namaste.