Упаковочный скотч и стретч-плёнка лежат рядом с воздушно-пузырчатой плёнкой.

Because the subject has two items joined by и:

• упаковочный скотч
• стретч-плёнка

In Russian, a subject like X и Y normally takes a plural verb, so лежат is the expected form.

Лежать literally means to lie, but Russian often uses it for objects that are simply resting somewhere, especially if they are not upright.

So here:

• лежат = they are lying / they are placed / they are located there

Compare:

• лежат — lying, resting somewhere
• стоят — standing upright
• находятся — are located, more neutral or formal

For tape and plastic film on a shelf, table, or in storage, лежат sounds very natural.

Because when рядом is followed by a noun, Russian normally uses the pattern:

рядом с + Instrumental case

So:

• рядом = nearby
• рядом с чем? = next to what?

In this sentence:

• рядом с воздушно-пузырчатой плёнкой = next to bubble wrap

You can use рядом by itself if no noun follows:

• Они лежат рядом. = They are nearby / next to each other.

Because рядом с requires the instrumental case.

The basic dictionary form is:

• воздушно-пузырчатая плёнка

But after рядом с, it changes to instrumental singular:

• воздушно-пузырчатой плёнкой

The endings change like this:

• -ая → -ой
• -а → -ой

So:

• воздушно-пузырчатая плёнка
• с воздушно-пузырчатой плёнкой

Russian adjectives must agree with the noun they describe in gender, number, and case.

Here are the two adjective+noun groups:

1. упаковочный скотч

   • скотч is masculine singular nominative
   • so the adjective is упаковочный

2. с воздушно-пузырчатой плёнкой

   • плёнкой is feminine singular instrumental
   • so the adjective is воздушно-пузырчатой

So the different endings are not random—they match the noun each adjective belongs to.

In everyday Russian, скотч usually means adhesive tape, especially clear sticky tape.

So:

• упаковочный скотч = packing tape / parcel tape

This word comes historically from the Scotch brand name, but in Russian it became a common noun.

A native English speaker may expect Scotch to mean whisky, but in Russian скотч normally means tape, not whisky.

They are hyphenated for different reasons.

• стретч-плёнка is a compound product name: stretch film
• воздушно-пузырчатая is a compound adjective meaning something like air-bubbled

Hyphenation is common in Russian with:

• borrowed first elements in product names
• compound descriptive adjectives

So these spellings are standard.

In стретч-плёнка, the borrowed element стретч stays unchanged, while плёнка is the part that behaves like the main noun.

For example:

• стретч-плёнка
• стретч-плёнки
• стретч-плёнкой

So if the whole expression changes case, it is mainly плёнка that changes.

In real Russian writing, ё is often written as е, so you may see:

• плёнка
• пленка

Both usually represent the same word, and the pronunciation is still плёнка.

Learners often prefer texts with ё because it makes pronunciation clearer.

Yes. Russian word order is fairly flexible.

The original sentence is a neutral way to say it:

• Упаковочный скотч и стретч-плёнка лежат рядом с воздушно-пузырчатой плёнкой.

But you could also say:

• Рядом с воздушно-пузырчатой плёнкой лежат упаковочный скотч и стретч-плёнка.

Both are grammatical. The difference is mainly in emphasis:

• the original starts with the items
• the second version highlights the location first

It can express both ideas at once.

Russian does not have a separate tense exactly like the English present continuous. So лежат can mean:

• are lying
• are located
• are sitting there

In this kind of sentence, it usually just describes where the objects are.