Yes you can give oats available in market. You can give it in many form like oats porridge, oats dosa, oats chila, oats pancake, masala oats with lots of veggies.

You can give her suji keer, makhana kheer, carrot puree, apple puree, mashed banana, mashed potato.

Teething phase is tough for babies. Just ho slow and offer different food at different interval. Massage his gums with clean wet fingers. You can try teether also.

ek fixed amount nahi rehta hai... solids dete waqt de sakte ho thoda thoda katke, aur din mein beech beech mein offer kar sakte ho... thode time baad baby khud paani keliye ishara karega... dhyan rahe ki khane ke ya breast milk dene ke just pehle paani naa de...

You can start with mashed banana and steamed apple.

-You can dry roast suji and can add jaggery into it.
-Boil and mash potato
-You can blend rice and can make kheer.
-Almond powder can be given.
-Try makhana kheer also

Yes absolutely !! If she doesn't like it than give few days to her and try again.

Do read these article. Water could be given on demand.You can give 4- 5 spoons after every meal.

Babies often reject food at this age but you keep trying. 4-5 times bm is enough if solids are also taken. Try new food items like suji kheer, makhana kheer, daliya etc. Encourage your child to move on his own as doc do not recommend walkers.

Nan pro is a very good option. Your baby is 8m now so start with good solid food too. Like Suji kheer, daliya and the same